Can't install Outlook

Posted on 1998-11-11
Medium Priority
Last Modified: 2010-04-08
Am getting error msg. at end of Outlook install: "comcat.dll not able to register itself in system registry" - I have completed 35 installs on very similarly configured machines without anything remotely like this.  Any suggestions?

Thanks.  JMMcNeil
Question by:jmmcneil

Expert Comment

ID: 1621912
Does this MS Knowledge Base article apply?

PSS ID Number: Q177805
Article last modified on 04-13-1998

The information in this article applies to:
 - Microsoft Outlook Windows NT client, version 8.03
When you install the Microsoft Outlook client on a Microsoft Exchange
Server computer, you may receive the following error:
   Setup cannot register COMCAT.dll in the system registry
   because an older version is in use. Close all applications
   and try again.
The Microsoft Exchange Event Service that uses the Comcat.dll file may be
running. This behavior is by design.
Stop the Microsoft Exchange Event service in the Control Panel Services
icon before starting or continuing with the Outlook installation.
Additional query words: ol97
Keywords          : XCLN
Version           : WinNT:8.03
Platform          : winnt
Issue type        : kbprb
Solution Type     : kbworkaround
Copyright Microsoft Corporation 1998.



Author Comment

ID: 1621913
The machine is running windows 95 so I don't know if this will apply or not.  It's worth checking into though.  Thanks.

Expert Comment

ID: 1621914
If you're not running WinNT then the Event Service doesn't apply.  However, the fact that comcat.dll is in use may.  Use Ctrl+Alt+Delete to see what else is running that might be using comcat.  Of course you should be sure NO other programs are running when you start the Outlook installation, especially any messaging or virus software.
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LVL 10

Expert Comment

ID: 1621915
You can always register comcat.dll manually...

run regsvr32.exe comcat.dll from your windows\system directory.  Then reinstall Outlook.  It will see that comcat.dll is already registered and does not need to upgrade it.


Author Comment

ID: 1621916
Thanks for the tips - I was able to get it to work by reinstalling from cdrom - had been using a network setup.  

Accepted Solution

linschoten earned 200 total points
ID: 1621917
I have done numerous installations of Outlook. A script installation is run when any of our 500 users logs onto the NT Domain. This error occurs quite rarely but is of no concern.
the COMCAT.DLL file is registered when Windows restarts.


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