Unable to log in to Vista workstation.

Issue

Unable to log in to Vista workstation. Get error message "Failed to init session: Class not registered".

Product Line

TAC Vista

Environment

Vista 4.XX

Cause

This normally occurs after having downgraded Vista. The problem is that a number of files are stored in the C:\Program Files\Common Files\TAC Shared folder and a version compatibility problem occurs. 

Resolution

  1. Uninstall Vista
  2. Locate the C:\Program Files\Common Files\TAC Shared folder
  3. Delete all the files in this folder
  4. Re-install Vista.