stop:c000021a {Fatal Error} The windows logon process system process terminated unexpectedly with a status of 0xc0000034(0x00000000)(0x00000000) Need Help Please System wont start up

You can make a bootable XP Recovery Console CD and replace the file, but it may be easier for you to make a Hren's boot CD.  

When you boot on the Hiren's CD, choose the Mini XP Mode and it has an XP style Explorer interface where you can search for and replace the suspicious or missing winlogon.exe file.

There should be a copy of winlogon.exe here:

c:\windows\system32\dllcache

Rename your current c:\windows\system32\winlogon.exe file (if there is one) and copy/paste the replacement from c:\windows\system32\dllcache.  If you don't see it there, search your HDD and find one.  Another possibility (depending on your environment) is c:\windows\ServicePackFiles\i386, or c:\i386 or d:\i386...

You just need to replace the winlogon.exe file somehow.

When you are done replacing, restart as usual (remove the bootable CD of course).

Using Hiren's, you can also copy off to an external USB device (thumb drive or HDD), any personal files for safety.

Make yourself a Hiren's BootCD which you can download from here:

http://www.hirensbootcd.net/

On the left, click Download, scroll down to the bottom, choose the latest version The download link is a little hard to see.  It is at the bottom of the page above the drop down list for older versions and looks like this (click this part to download the ZIP file:

Direct HTTP Mirror + Torrent + Torrent Magnet

Click the "Direct HTTP Mirror" link to start the download and save the ZIP file to your desktop of someplace you can remember.

The ZIP file is large, so the download will probably take a little while to complete.  Then unzip the download to extract the Hirens.BootCD.ISO file that will be used to create your new bootable CD.

Creating a bootable CD from a .ISO file is not the same as just copying the .ISO file to a blank CD.  You have to use software that understands how to burn a .ISO file to a CD to create a bootable CD.

In the Hiren's ZIP file are the BurnToCD.cmd file that you can double click to launch it.  The BurnToCD.cmd will use the extracted BurnCDCC.exe file to burn the .ISO file to a blank CD using your existing CD burner.  You can also use your own CD burning software as long as your software is capable of creating a bootable CD from a .ISO file.  Most modern CD burning programs can create bootable CDs from an .ISO image.  Creating a bootable CD from an ISO image is not the same as just burning the file to a CD.

If you need a free and easy CD burning software package, here is a popular free program:

http://www.imgburn.com/

Here are some instructions for ImgBurn:

http://forum.imgburn.com/index.php?showtopic=61

It would be a good idea to test your new bootable CD on a computer that is working.

You may need to adjust the computer BIOS settings to use the CD ROM drive as the first boot device instead of the hard disk.  

These adjustments are  made before Windows tries to load.  If you miss it, you will have to reboot the system again.

When booting on the Hiren's CD you will see a menu of options.  Choose the Mini XP option.  Then it will appear that Windows is being loaded and you will be presented with a desktop that has the look and feel of the Windows Explorer interface you are already used to using.

Using the Mini XP, you can access the Internet, maneuver around your system, search for files, copy files, replace files, run various scans for malicious software, edit text files (like the c:\boot.ini) etc.  

There are dozens of free and useful tools included in the CD that can be used to repair your system or copy your important personal files to another device (like a USB device or external drive) in the event that you just give up and decide to reinstall your XP (hopefully you will not make that decision).

Do, or do not. There is no try.

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