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When I turn my Windows XP Professional PC on it goes past the Windows XP loading screen then I get blue screen of death with the error C000021a the session manager initialization system process terminated unexpectedly with a status of 0xc000003a I have no idea what the error means or how to fix it any help would be appreciated

I have tried to boot off Windows XP and recovery mody chkdsk /r but this didn't fix it

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Did you try system restore? – Dennis Dec 15 '11 at 16:02
how do i do this if i cant login to windows? – ben950 Dec 15 '11 at 16:03
i have a feeling it has something to do with a hidden partition anybody how how to unhide it? – ben950 Dec 15 '11 at 16:09
Can you get in in Safe Mode? Did chkdsk find ANY errors? – Ƭᴇcʜιᴇ007 Dec 15 '11 at 16:24
it will not let me boot into safe mode it mestions that is is missing autochk. what is sfc i havent heard of that before ?? – ben950 Dec 15 '11 at 16:26
up vote 3 down vote accepted

Things you can try:

  • Restore to last known good configuration:

    When booting, press [F8] right after hearing the "beep" and select Last Known Good Configuration.

  • Use System Restore:

    When booting, press [F8] right after hearing the "beep" and select Safe mode with a Command prompt, the execute %systemroot%\system32\restore\rstrui.exe.

  • If none of the above works, boot from the Windows XP installation disc and choose R for Recovery console and execute the following commands (source):

    md tmp
    copy c:\windows\system32\config\system c:\windows\tmp\system.bak
    copy c:\windows\system32\config\software c:\windows\tmp\software.bak
    copy c:\windows\system32\config\sam c:\windows\tmp\sam.bak
    copy c:\windows\system32\config\security c:\windows\tmp\security.bak
    copy c:\windows\system32\config\default c:\windows\tmp\default.bak
    delete c:\windows\system32\config\system
    delete c:\windows\system32\config\software
    delete c:\windows\system32\config\sam
    delete c:\windows\system32\config\security
    delete c:\windows\system32\config\default
    copy c:\windows\repair\system c:\windows\system32\config\system
    copy c:\windows\repair\software c:\windows\system32\config\software
    copy c:\windows\repair\sam c:\windows\system32\config\sam
    copy c:\windows\repair\security c:\windows\system32\config\security
    copy c:\windows\repair\default c:\windows\system32\config\default

    then try again.

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i have tried these but same result. when i put md tmp nothing acutlay happened but all other commands worked – ben950 Dec 15 '11 at 17:01

If the suggestion by Dennis does not work

How to do a Manual SYSTEM RESTORE in XP

A. Connect your non-bootable hard drive to another computer, as a secondary drive or use a usb adapter or enclosure, If you can see your data on the drive, back it up Now, then follow the rest of these instructions.

B. Open Windows Explorer. Click on Tools|Folder Options|View. Check the box beside "Show hidden files and folders". Apply your change.

NOTE D: may not represent the hard drive you connected to your PC, it may be E: or F: or G:, it all depends on how many other drives (including cd/dvd) you have in your host PC, So substitute the appropriate drive letter in the instructions below.

C. Navigate to the D:\System Volume Information folder. You will see a folder named something like _restore{.........} the dots represent an alpha-numeric sequence.

In this folder you will see folders named RP0....RPnn. Find the one with the highest number.

These are your System Restore points. In the highest numbered folder you will see a folder named snapshot. In this folder are registry hive files which you need to recover your system:






D. Create a subdirectory; i.e, D:\Windows\TMP. Copy these files to the TMP subdirectory. Rename them to:






Note Be sure to lose the period (.) in the file named _registry_user_.default

E. Delete the files in the D:\windows\system32\config subdirectory with the same short names.

F. Copy the D:\windows\tmp files to the D:\windows\system32\config. subdirectory.

G.Put your drive back in its original system. Your system should start normally. If you get the same error repeat the procedure and choose another folder ( RPnn) (next highest number). You can repeat this procedure choosing lower RPnn numbers until you get it booting again.

If you are denied access to any folders you will have to take "Ownership" of the folders first.

If this procedure fails to work you need to repair or reinstall Windows.

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