A growing trend among Windows XP SP2 and SP3 users is Windows XP is logging in when username and/or password is entered...but then it logs right back out. There are a large list of fixes that are included to help you solve this problem.

This thread should be popularized by tech experts, who know about this issue and can provide fixes. Users needing fixed, should not post here in this topic but start their own topic in this Windows XP forum.

Users needing help should check here first for fixes, and try all the fixes, before continuing with help.

Download RC.ISO and save it somewhere you can find it.

Download MagicISO and install it.

Start MagicISO. When it asks you to register, just close that window...the
program should remain open. Click on "File" and then on "Open"...navigate to the RC.ISO file you downloaded, select it, and click "Open".

In the upper right pane, double click on the i386 folder to expand it. In the toolbar menu, click on the "Add File" icon (just under "Total Size: 7M") and navigate to C:\Windows\System32...locate and select userinit.exe...click "Open".

Click "File" on the toolbar and choose "Save As". Name the file RCplus and save it somewhere you can find it.

Put a blank CD-R disk in your CD burner and close the tray...when the AutoPlay window opens, close it.

Click "Tools" on the toolbar and choose "Burn CD/DVD with ISO". In the CD/DVD Image file area, click the little folder, navigate to the newly created
RCplus.iso image file, and click "Open". In the CD/DVD Writing Speed
drop-down menu, choose the top 8X setting. Format should have "Mode 1"
selected...if not, select it. Click on the "Burn It!" button.



Once this disk is burned, put it in the machine you're working on and restart. Boot to the CD just as you did with the OEM disk and enter Recovery Console just as you did before.

At the C:\Windows> prompt, Type the following commands, pressing Enter after each one. Again, note the spaces.

d:
cd i386
copy userinit.exe c:\windows\system32
exit

After inputting the third command, you should receive the message "1 file
copied"...which will indicate that the operation succeeded.

See if Windows will let you log on.

Boot to the XP cd.

At the Welcome to Setup screen, press R to repair using Recovery Console.

Select the operating system to log on to by number...usually 1...press Enter.

When prompted for the Administrator password, leave it blank and press Enter.

At
the prompt C:\Windows>, type the following commands pressing Enter
after each one: (Note the spaces in these commands...they are
important. Also note that I am assuming that your cd drive is drive d:.
If it's not, substitute the drive letter that represents your cd drive
in place of d:.)

d:
cd i386
expand userinit.ex_ c:\windows\system32 <--there is a space after ex_
exit

After
inputting the third command, you should receive the message "1 file
copied"...which will indicate that the operation succeeded.

See if Windows will let you log on.

(Credit to wannabe1 at GeeksToGo)

SHOULD ONLY BE USED IF INSTRUCTED BY TECH GURU

I think we're looking at a corrupt, missing, or
overwritten explorer.exe file...and that may not be the only exe that's
been overwritten. It's hard to tell when things won't open.

Let's
make another disk the same way you made the last one. This time instead
of copying the userinit file, navigate to C:\Windows and copy
explorer.exe to the RC.ISO disk.

Boot to Recovery Console as you did before using the new disk and use the following commands:

d:
cd i386
copy explorer.exe c:\windows
exit

When you type the third command, you should be prompted for whether you want to overwrite the current file....type Y and press Enter

Let the machine try to boot normally.

(Credit to wannabe1 at GeeksToGo)

USE ONLY IF INSTRUCTED BY MALWARE REMOVAL TEAM

You have a Win/32 Virut infection. If all steps in this forum have been tried and nothing else works, and it seems like a lot of your files are missing or corrupted...then Virut may be your problem.

Users are prompted to reformat/reinstall Windows.

FOLLOWUP FOR VIRUT INFECTION FOR USE BY MRT TEAM ONLY

Do you have an external hard drive available to you or can you purchase an external enclosure to put your hard drive into?

The
two easiest ways to get your files would be to use a live linux distro
and copy the files to an external hard drive...or put your hard drive
into an external enclosure and copy the files to another machine until
we get an operating system back on yours.

The latter choice is
the easiest of the two. You don't want to copy any exe files or scr
files, though. Those are the ones that virut infects and is why it is
such a nasty virus. It's difficult to detect until you see the effects
and by then it's nearly impossible to remove. As you have seen, nothing
works...and that's what virut counts on.

With your recovery cd,
you should be able to get your machine back up and running right pretty
quickly. Then you can move your data back on and make yourself at home
again.

(Credit: wannabe1 at GeeksToGo)

Backup and clean reinstall of Windows. (no infection, but if all methods do not work, this is last resort)