Microsoft KB Archive/247649

From BetaArchive Wiki
Knowledge Base

Article ID: 247649

Article Last Modified on 8/15/2005


  • Microsoft Visual Studio 6.0 Enterprise Edition

This article was previously published under Q247649


When running Visual Studio 6.0 setup on Windows NT 4.0 you may receive the following error message:

MSCAL.OCX was unable to register itself in the system registry.

Setup may continue, but the following error message appears:

Visual Studio 6.0 setup was not completed successfully


Mscal.ocx does not register under certain circumstances with version 5.0 of Comcat.dll.


Use the following steps to replace Comcat.dll version 5.0 with version 4.71.1460.1. Replace C:\ with the Windows NT installation drive if Windows NT is installed to a different drive on your computer.

  1. From the Start button, click Run. Type cmd and click OK.
  2. Rename the file C:\WINNT\System32\Comcat.dll to Comcat.123
  3. Copy the file Comcat.dll (ver. 4.71.1460.1) to the Windows System folder on your machine. Comcat.dll is located in the folder VB98\Wizards\PDWizard\Redist\ on Disk 1 of the Visual Studio/Visual Basic 6.0 CD.
  4. From the Start menu, click Run. Type REGSVR32 COMCAT.DLL and click OK.
  5. Restart the computer.
  6. Reinstall Visual Studio 6.0.


This issue has been seen on Service Pack 3,4, and 5 machines.

Additional query words: mscal mscal.ocx

Keywords: kbprb KB247649