Using Add/Remove Programs and Add/Remove Windows Components, you see this message:
Setup library msdtcstp.dll could not be loaded, of function OcEntry could not be found.
Contact your system administrator. The specific error code is 0x7e.
The msdtcstp.dll file is either missing or corrupt, your system PATH variable is incorrect or your system is afflicted with malicious software (or all of the above).
Using Windows Explorer, browse and see if the file is present.
The msdtcstp.dll file should be in this folder:
c:\windows\system32\setup
Since it is one of the 3498 files that is covered under Windows File Protection, if it ever was installed and working, it should never be "missing" unless something else is wrong, but you can just go ahead and replace it with a known good copy and then work on any remaining issues.
You can search your system for copies of msdtcstp.dll and copy one into the correct folder replacing the missing or suspicious file. You need to replace the file if it is missing, or overwrite the afflicted file if it is suspicious.
There should be a a copy of msdtcstp.dll file in this folder:
c:\windows\system32\dllcache
Just copy c:\windows\system32\dllcache\msdtcstp.dll and paste it into the c:\windows\system32\setup folder to replace it.
Respond in the affirmative if asked to overwrite the existing file.
Test your system now.
If you can't find the file and have a genuine bootable XP installation CD installed and the CD is drive X, expand the file from the i386 folder on the CD into your c:\windows\system32\setup folder by entering this command from a Command Prompt window:
expand x:\i386\msdtcstp.dl_ c:\windows\system32\setup\msdtcstp.dll
Respond in the affirmative if asked to overwrite the existing file and then you should see a message that 1 file(s) was expanded.
Test your system now.
Please report back your results.
Your system could also be afflicted with malicious software, so follow up your resolution with this:
Download, install, update and do a full scan with these free malware
detection programs:
Malwarebytes (MBAM): http://malwarebytes.org/
SUPERAntiSpyware: (SAS): http://www.superantispyware.com/
They can be uninstalled later if desired.
When the scans run clean, then troubleshoot any remaining issues.
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