Issue
Unable to log in to Vista workstation. Get error message "Failed to init session: Class not registered".
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
- Uninstall Vista
- Locate the C:\Program Files\Common Files\TAC Shared folder
- Delete all the files in this folder
- Re-install Vista.