Patches and updates

Comcat.dll update for Windows Intel NT installation problems

Published: February 11, 2000


Comcat.dll update for ArcInfo 8.0.1, 8.0.2 or ArcGIS 8.1 Windows Intel NT installation problems. If, after installing ArcInfo 8.0.1 or 8.0.2 and rebooting, you get an "error configuring ArcInfo" message, you'll need this software update. If you're installing ArcGIS 8.1 and a message appears stating the comcat.dll is the wrong version, you'll need this software update.


Some software applications are installing incompatible versions of Ole32.dll and Comcat.dll, causing errors with other software applications such as ArcInfo.

For ArcInfo 8.0.1 and 8.0.2

After installing ArcInfo 8.0.1 or 8.0.2, if you get DLL registration errors after reboot, followed by a runtime error, you may have mismatched versions of Ole32.dll and Comcat.dll.

This error will also cause the following problems upon trying to start the applications (e.g. ArcMap or ArcCatalog):

        Microsoft Visual C++ Runtime Library -          Runtime Error!          Program: C:\arcexe80\bin\ArcMap.exe          abnormal program termination 

For ArcGIS 8.1

If the files are incompatible when you install, you'll receive a message. If you install something after ArcGIS 8.1 that updates either incorrectly, you may encounter the following error upon trying to start the applications (e.g. ArcMap or ArcCatalog):

          Microsoft Visual C++ Runtime Library -            Runtime Error!            Program: c:\arcgis\arcexe81\bin\ArcMap.exe            abnormal program termination

Compatible versions

The compatible versions of these dlls installed by Microsoft Windows NT are:

  • Comcat.dll version 4.71 and Ole32.dll version 4.0

To determine the version of these dlls on your machine, right click on the file names (e.g., Comcat.dll and Ole32.dll), located under c:\WINNT\system32, click on Properties, and click on the Version tab.

If you do not have version 4.71 of Comcat.dll, you will need to install it.

To replace the Comcat.dll with the proper version

  1. If you have already installed ArcInfo, uninstall it.
  2. Download and unzip the Comcat.dll (ZIP format, 9kb) to your c:\temp folder.
  3. Open a Command Prompt. Click Start > Programs > Command Prompt, and type
    cd c:
  4. Change to the location of the system32 folder
    cd c:\winnt\system32
  5. Rename the existing Comcat.dll
    ren Comcat.dll Comcat.dll_bak
  6. Copy the Comcat.dll version 4.71 that you downloaded to thec:\winnt\system32 folder
    copy c:\temp\Comcat.dll Comcat.dll
  7. Close the Command Prompt window by typing exit
  8. Reboot computer
  9. Re-install ArcInfo

Download ID:86

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