Reinstalling COM+ on Windows XP

I’ve been experiencing some problems with COM+.  I noticed a
problem this week when I went to open an ASP.NET application in Visual
Studio.NET (I haven’t been developing web apps for a while). 
After some investigation I found out that IIS 5.1 was not serving ASP
and ASPX pages and the event log was spitting out nasty error messages about COM+ being corrupted.

There’s lots of information out there on the Internet about
reinstalling COM+ on Windows 2000 but the instructions for Windows XP
weren’t clear.  I read in a few places that you need to remove the
COM+ catalogs, remove a registry key, re-register the OLE server DLLs
and then “Add/Remove Windows Components”.  When I went looking for
a check box option for COM+ services in “Add/Remove Windows Components”
I didn’t find it anywhere, which is what I expected because COM+ is
built into XP, unlike Win2K.  What I failed to understand at the
time was that simply clicking next on the add/remove wizard will cause
Windows to rebuild COM+ catalogs and registry entries.

I found the solution (one of many, as mentioned) on Symantec’s web
, of all places.  It seems that Ghost 9.0 sometimes comes
across the corrupted COM+ problem. Below are the instructions with my annotations:

  1. Start Windows Explorer.
  2. Do one of the following:
    • In Windows 2000, browse to the C:WinntSystem32 folder.
    • In Windows XP/2003, browse to the C:WindowsSystem32 folder.
  3. Right-click the Clbcatq.dll file, and then click Rename.
  4. Rename the file to ~Clbcatq.dll.
    Make sure that you include the tilde (~) at the start of the file name.
  5. Restart the computer.
    Restart in safe mode so that the COM+ catalogs can be removed without the files being locked.

  6. On the Windows taskbar, click Start > Run.
  7. In the Open box, type regedt32 and then click OK.
  8. In the Registry Editor, find and delete the following key:


    As a safety measure, I renamed my key to something else.

  9. Exit the Registry Editor.
  10. Click Start > Run.
  11. In the Open box, type cmd and then click OK.
  12. At the command prompt, type the following lines, pressing Enter after each line:

    cd %windir%
    rmdir /s registration

  13. Close the DOS Window.
  14. Start Windows Explorer.
  15. Do one of the following:
    • In Windows 2000, browse to the C:WinntSystem32 folder.
    • In Windows XP/2003, browse to the C:WindowsSystem32 folder.
  16. For each of the following files, right-click the file and choose Copy, find the Regsvr32.exe file, right-click it and choose Paste.
    • Ole32.dll
    • Oleaut32.dll
  17. Restart the computer.
    Exit out of safe mode, COM+ doesn’t install properly in safe
    mode. Worked for me in normal mode with logged on user with
    administrative rights
  18. Click Start > Settings > Control Panel.
  19. Double-click Add/Remove Programs.
  20. Click Add/Remove Windows Components.
  21. Click Next to proceed with reinstallation.
    This will refresh your COM installation.
  22. Check the COM+ services are started (run SERVICES.MSC from Start button, run).
    I set both of the two COM+ services to start automatically.
  23. See if you can browse the COM+ components on the local machine in Component Services, under Control Panel, Administrative Tools.

53 thoughts on “Reinstalling COM+ on Windows XP

  1. http://

    This is the worst instruction I’ve ever encountered. I followed the instructions exactly and no sooner after I rename the clbcatq.dll file my computer froze up. Would freeze every time I tried to log in. This is a work computer and THANK YOU VERY MUCH FOR GETTING ME FIRED!

  2. http://

    My apologies.
    <br>I have a dell computer and turns out that if the keyboard is not from dell as well, the computer freezes up in safe mode. I followed the rest of the method and it worked perfectly. Sorry about my hastiness in posting. Just want everyone to know that I tried this on a Windows XP machine and it worked.

  3. http://

    <br>I followed the instructions but when i reinstall COM+ i have an error and my IIS is still not able to compile ASP pages.
    <br>do you suggest me to reinstall windows? any help will be appreciated
    <br>thank you

  4. Rob Garrett

    Okay, been busy and haven’t had chance to reply here, but here goes.
    <br>1. These instructions are not mine, I found them on Symantec’s website – if you’re computer is hosed because of corrupted COM and these instructions either don’t help or make your problem worse, then don’t blame me – call Symantec.
    <br>2. When messing with the registry, or COM infrastructure, there is always a chance that your computer will become unusable. Backup your computer first (duh). If you’re attempting to fix a work computer, my suggestion would be to call your tech support. If you are tech support, then either call Microsoft or search Google (which is what I did).
    <br>3. I’m not going to advise that anyone reinstall their computer – this is the last resort, and if you feel that this is the only avenue left to take then you should make that decision yourself. I remain blameless for the loss of any data, or failure to correct the problem, due to a reinstall

  5. http://

    Actually, these instructions work fine and WILL get the COM+ service working again.
    <br>By the way, you CAN view the COM+ checkbox in Add/Remove Programs &gt; Add/Remove Windows Components by doing the following:
    <br>Use Notepad to remove Hide from the COM= line in %SystemRoot%InfSysoc.inf
    <br>Before Editing: com=comsetup.dll,OcEntry,comnt5.inf, hide, 7
    <br>After Editing: com=comsetup.dll,OcEntry,comnt5.inf, 7
    <br>Removing the word &quot;hide&quot; just makes the COM+ option checkbox visible in the Add/Remove dialog box.
    <br>However, you need to do a bit extra in order to get ASP and ASP.NET fully working again. Here’s what yo udo next as part of the FULL fix to the issue:
    <br>Step One:
    <br>Check Event Log:
    <br>Check your Event Viewer for these errors…
    <br>MSDTC errors (4427,4691,4135 are common error events for this)
    <br>W3SVC Event 36 &quot;The server failed to load application ‘/LM/W3SVC/1/ROOT/’. The error was ‘Class not registered&quot;
    <br>Step Two:
    <br>Open &quot;Control Panel&quot; and then &quot;Administrative Tools&quot; then Open &quot;Services&quot;…
    <br>Locate the &quot;Distributed Transaction Coordinator&quot; make sure the process is &quot;Started&quot; and &quot;Automatic&quot;
    <br>(If its not, open a command line and type &quot;msdtc -install&quot;, then try and start the service)
    <br>Open a command line and type the following…
    <br>cd %windir%system32inetsrv
    <br>rundll32 wamreg.dll, CreateIISPackage
    <br>(NOTE: &quot;CreateIISPackage&quot; must be typed exactly; it is case-sensitive.)
    <br>regsvr32 asptxn.dll
    <br>(wait for a dialog box to notify you asptxn has registered correctly)
    <br>Then, in the cmd prompt window type IISRESET
    <br>Open &quot;Control Panel&quot; then &quot;Component Services&quot;…
    <br>You should see all three IIS COM+ applications that have been recreated
    <br>Finally, open &quot;Control Panel&quot; and then &quot;Administrative Tools&quot; then Open &quot;Services&quot; and just make sure that
    <br>World Wide Web Publishing
    <br>are all running…..
    <br>As a very final check just stop and restart the web service in IIS itself.
    <br>With a bit of luck the COM+ and ASP/ASP.NET issue should be resolved.

  6. http://

    Cheers Rob and nice one for having this blog and allowing folks to share knowledge.
    <br>I work for a software house in Regent Street in London developing web-based content management systems and got the shock of my life when I fired up Visual Studio.NET this weekend to do a bit of work 🙁
    <br>What is bugging me now is what caused it to happen in the first place and could it happen again?
    <br>Was it a Windows update that went wrong, a software install (I recently put in PGP, Open Office and some XML development tools) or is this just a seemingly random issue?
    <br>Anyway, once again thanks for letting me share what I found and I hope it works for others.

  7. Rob Garrett

    Hmmm, I wish I knew what causes COM+ corruption. I found mine on my server when I installed OWA with Exchange. None of the web links nor spell check worked because ASP was broken. After some searching on Google I found out that this was because COM+ was corrupted. From what I read, it could be any installation that went wrong.
    <br>Always a pleasure talking with someone from my home land 🙂

  8. http://

    I had COM+ screwed up on XP computer. Could not run ASP.NET. I followed your instructions and COM+ got fixed. Thanks a lot !

  9. Rob Garrett

    Glad that this post was useful.
    <br>It seems that a lot of people are having problems with broken COM+, and I am happy that my post is of great help to those people frustrated with this problem.

  10. http://

    Great post…I would like to note that removing the Registration command gave me a sharing conflict (yes even under safemode) and so I rebooted into Safemode once again and was able to take care of it.
    <br>I also followed Andy’s post, but I’d like to note (for anyone curious) that even though it shows up in Add/Remove, it would allow me to uncheck it, so I’m not sure there’s value to the visibility.
    <br>Thanks again!

  11. http://

    <br>actually meant:
    <br>&quot;it would NOT allow me to uncheck it, so I’m not sure there’s value to the visibility.&quot;

  12. http://

    <br>I’ve been trying to follow these instructions to reinstall COM+, but it doesn’t seem to work for me.
    <br>While it is attempting to install COM+, it gets an error:
    <br>Sub-component COM+ raised an exception while processing the OC_COMPLETE_INSTALLATION setup message.
    <br>d:ntcom1xsrccmplussetupcomsetupccompluscore.cpp (line 565)
    <br>Error Code = 0x80040206
    <br>An unexpected internal error was detected
    <br>The COM+ eventclasses could not be registered
    <br>I am also having issues with MSI, but I’m not sure if the root cause is in COM+ or in MSI, or something else.
    <br>This all started when I tried to install Norton 2006, and my computer has been toast ever since. The failed install seems to have screwed up some registry protections – I have followed everything I can find on the Symantec website, including manual un-install and attempted re-install, but I’m still stumped.
    <br>Any ideas much appreciated…
    <br>Thanks, Mike
    <br>PS I had similar problems with lockups in safe mode, I used &quot;safe mode with command line&quot; and it seemed to work better, I’m not exactly sure why.

  13. Rob Garrett

    Eek, that doesn’t sound too good. Have you tried reinstalling the MSI installer? You might want to drop Symantec a line and tell them about Norton.
    <br>I hate to chime an old note, but if you’re a Norton fan, I would suggest buying a copy of Ghost, and imaging your machine before installing system apps. This was the best purchase I’ve ever made and has saved me hours of not having to resinstall the OS.

  14. http://

    Yes, I tried reinstalling the MSI installer, no good.
    <br>I dropped Symantec a few lines of gradually increasing frustration, unfortunately they were not able to help.
    <br>I’ve now reinstalled Windows (&quot;repair&quot; install, not install from scratch), and it’s looking better but still not quite there. I suspect that there are still some lingering registry permission issues; I guess a Windows repair install does not necessarily reset all the protections. Anyway it’s limping alomg now…
    <br>At this point I am the polar opposite of a Norton fan 🙁

  15. http://

    Finally i got my iis 5.1 working on windowsXP. Thanks to this tutorial, and one comment. It took me almost a hole day, but i am glad that at least i didn’t have to reinstall XP. I already was thinkin about reinstalling XP or using vmware or another pc to do my work. That could have taken me few more days… So i very apreciate for this post.

  16. http://

    <br>I wasted hours on the phone with MS tech support yesterday trying to get this problem figured out. Each person I talked to passed me on to another, whom they said was part of their &quot;IIS&quot; team. I lost my temper when the second to last person asked me what IIS was. The outcome? Not one of the 10 or so people I talked to could help me, they wasted several hours of my time, and in the end some woman told me, &quot;That sounds like a professional problem, we’re going to have to charge you $245 to figure it out&quot; WTH? Screw MS tech support! Yes, I’m a little bitter…
    <br>Anyway, I had tried multiple things on my own, including fixes from the MS website. This finally did the trick (along with Andy’s followup instructions). Thankyou, thankyou, thankyou!

  17. Harald

    Hey Rob and Andy!
    <br>Got COM+ and ASP.NET up and running again thanks to your instructions after a failed SP 2 installation. Was just about to insert the CD for an other repair session – Ugh. Thanks a lot!

  18. http://

    COM+ Setup Error
    <br>Sub-component COM+ raised an exception while processing the
    <br>OC_COMPLETE_INSTALLATION setup message.
    <br>d:ntcomcom1xsrccomplussetupcomsetupccompluscore.cpp (line 565)
    <br>Error code = 0x80040206
    <br>An unexpected internal error was detected
    <br>The COM+ event classes could not be registered.
    <br>Anybody has ideas on how to get COM+ reinstalled ?

  19. http://

    I went through the procedure posted above but I still have the same problem. When I open COM in component services I get an error and IIS still won’t server up asp pages. I am running Windows XP Media center edition IIS 5.1 . Anyone know if media center edition causes unique problems??

  20. http://

    Thank You!!! I just got a new computer with XP Media Center 2005. I installed IIS and got the dreaded 500 error while trying to run ASP/ASPX pages. After days of looking for the solution, I finally found this article. It fixed my issue immediately. Thanks again!

  21. http://

    Thanks ! It worked great. Just for those having trouble with MSI & Com+ installation, be sure to hava document & settings available (not redirected to a network share…)

  22. http://

    Have tried several varients of the above fix, but keep getting

    Sub-component COM+ raised an exception while processing the

    d:ntcomcom1xsrccomplussetupcomsetupccompluscore.cpp (line 565)
    Error code = 0x80040206

    An unexpected internal error was detected
    The COM+ event classes could not be registered.

    I can’t get detail from the app log (because com+ is dead?) and I can’t do an uninstall of the last program I installed just before everything died as the installer is dead too.

    Using XP SP2 on a new Dell 820

  23. http://

    I also have the same error as Peter and have tried all variations of the fix but continue to have the same problem.
    I can do the uninstall steps ok in safe mode but I blue screen with a memory dump when trying to log in as non-safe mode. I suspect the non-safe mode is trying to load services which are dependent on COM+ that are giving memory errors.
    I was going to disable all services in safe mode and try again. After a severe virus attack that blew my PSC and Mobo, I’ve already spent the guts of 2 months trying to get back to a working pc, so any suggestions would be greatly appreciated.
    I am also getting failures on the Microsoft update screen if that clue helps any.

  24. Roelf

    I have merged 2 patitions into one on a customers HDD (FAT32) using partition magic.
    after the merge the pc continues to reboot just after xp started to load, I run windows repair (home edition) and 20 min before the end I get the com+ error msg.

    I have started the computer using ERD Commander and did the changes in your BLOG, but still get the same problems.

    anyone having any idea what else I can try, pls let me know.

    Thanx for a great blog?


  25. http://

    I found the following on Mohamed Sharaf’s Blog. After following the above suggestions, I was still getting errors when trying to expand Component Services and MSDTC would not appear under Services (Local). I followed these instructions and I can now expand Component Services and MSDTC appears under Services )Local).

    ASP and ASP.NET may not work if IIS is installed After Windows XP SP2
    Primary Common issue associated with:

    Distributed Component Model (DCOM)

    Primary Audience issue associated with:


    Scenario / Issue

    If MSDTC is not running as NetworkService then ASP and ASP. NET will not work on a Windows XP SP2 machine. MSDTC might not be running as NetworkService if IIS is installed AFTER you install Windows XP Service Pack 2.

    You might receive the following error when accessing a web page from this machine:

    [The page cannot be displayed

    The page you are looking for is currently unavailable. The Web site might be experiencing technical difficulties, or you may need to adjust your browser settings.]

    WinSE 69962

    Summary of Resolution

    To resolve the issue you must uninstall MSDTC, clean the registry entries for MSDTC then reinstall IIS.

    Reproduction and Resolution Steps

    Steps to resolve the issue.

    From the command line issue a ‘Net stop msdtc’ command.

    From the command line issue a ‘msdtc -uninstall’ command.

    Using Regedit, delete the key, including all of its subkeys and values, HKLMSoftwareMicrosoftMSDTC.

    From the command line issue ‘msdtc -install’.

    From the command line issue ‘net start msdtc’.

    Uninstall IIS from the Add/Remove Windows Components.
    Reinstall IIS from the Add/Remove Windows Components.

  26. http://

    Thanks a lot Rob Garret.

    I followed the steps 1 by 1 and it is solved.

    Note: I excluded safe mode step, because it freezed in safe mode. Besides it still worked for me.

  27. http://

    What do I do if I can’t rename cltcatq.dll on a normal boot or safe mode? I’m in Windows 2000, it tells me the file is in use by windows.

  28. Brandon B.

    Something I’ve found, in Win2k… if by some strange reason your Clbcatq.dll is in use by windows, you can crack open notepad, dump a few characters into a file and save it as ~Clbcatq.dll and that works too.

  29. http://

    Have tried all the above but same as Peter got the error:

    Sub-component COM+ raised an exception while processing the OC_COMPLETE_INSTALLATION setup message.

    d:ntcomcom1xsrccomplussetupcomsetupccompluscore.cpp (line 565)

    Error Code = 0x80040206

    An unexpected internal error was detected

    The COM+ event classes could not be registered.

    Was anyone able to solve that?
    To rule out disk errors had them scanned on boot
    To rule out MS file corruption cmd -> sfc.exe /Scannow

    Hope there’s someone out there who’s fixed it,…

  30. http://

    Just used your instructions to fix corrupt COM+ on XP w/SP2. The comment about going into Safe Mode did the trick. Thank you so much Rob!

  31. http://

    To those guys who have this error:
    “Sub-component COM+ raised an exception while processing the

    d:ntcomcom1xsrccomplussetupcomsetupccompluscore.cpp (line 565)
    Error code = 0x80040206

    An unexpected internal error was detected
    The COM+ event classes could not be registered. ”

    I had a problem with some virus on my laptop. It corrupted almost all registry. After antivirus procedures and repairing Windows from the disks everything seemed worked fine. After automatic updates completed and system restarted a problem appeared with Windows Installer Service that it could not be accessed.
    Finally I discovered that the problem was in corrupted COM+. Followed the instructions here got the above error.
    You should just click OK and proceed further with installation, then restart.
    Finally, windows installer start working and was able to reinstall .NET 2 and all the patches.

    Thanks for post.

  32. http://

    Grreeeeaaaat…. I was able to resolve the problem quickly with the help of this article…. Long live the author

  33. http://

    Great article, my friend. Windows can be such a frustrating platform for developers. My local IIS decided to die yesterday because of this COM+ issue and your article saved me a lot of time resolving the problem.

  34. http://

    Many thanks from across the sea in Daytona Beach, FL. I’ve been fighting the COM+, MSDTC and W3SVC errors for almost a week on one of my computers. Your simple steps worked perfectly.
    Thanks again.

  35. http://

    I have been troubleshooting for weeks a problem trying to run an IIS app. I zeroed in on it being a COM+ problem…and followed Andy’s instructions…problem fixed…thank you both for taking the time to post the info…it is really appreciated…and it should make you feel good to know you have helped others.

  36. http://

    Hello, I really need your help:
    Did you find what may have had caused this? I have the same problem, I installed IIS and others programs the same day, then I noticed that IIS didn’t run, it had a red X in the default web site icon and the component services didn’t run either. All I got in the COM+ Application was this buggy message: “An error ocurred while processing the last operation. Error code 8004E00F -COM+ was unable to talk to the Microsoft Distributed Transaction Coordinator.
    The event log may contain additional troubleshooting information”
    Could it be related to the problem you had? The machine I have to fix is a customer’s PC so I wouldn’t dare to do all these steps directly on his PC, but I haven’t being able to reproduce the same error on my PC so I could pratice and verify that the steps you have shared in this bolg will work for his PC. How could I make my PC have the same behaviour so I could test every steps before going to my client?

  37. http://

    My customer had installed Sym,antec ANtivirus , it seems to be the proble. I’ll try it. So much thanks for this blog!!!!!!!

  38. http://

    Rob, thanks for pointing me in the right direction regarding this problem. At first I got the same installation failure/error as Mike, Svein, Peter Fouche and Sprize but after starting the DCOM Server Process Launcher service, which I had set to Manual, the re-installation finished successfully!

  39. http://

    Alexander said:

    “You should just click OK and proceed further with installation, then restart.”

    I don’t understand what you meant with this. When I click “ok”, the install finishes on its own and there is no way back INTO the install to “proceed further” with it.

    The problem is driving me round the bend. It (the COM+ error) happened when I wanted to back up the registry, and this COM+ issue surfaced when I tried to find out what the backup error meant.


  40. http://

    Thank you very much. I was about to format my HD but your instructions saved my XP installation. All working fine again.

  41. Tan

    Many thanks Bob!! Trying to recover from Zaccess Trojan infection. Your instruction save my XP installation even in Nov-2012 now. I found that Step 16 not working though (Regsvr32.exe somehow does not accept dll file???) and maybe not necessary.

  42. ZEE

    Dude… you rock… even 8 years after… don’t mind if this was from Symantech… your site was the first where i found this and working…. ROCK!!!! thanx —->> ZEE

  43. dan

    thanks you very much for your post
    dcomcnfg.exe is running again after a long time searching solution

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