TROUBLESHOOTING

.VSTO Error when installing the Outlook plug-in

Issue

.VSTO Error when trying to install the Outlook plug-in

Objective

Environment

  • Windows 7
  • Outlook 2010, 2013
  • GoToMeeting

Procedure

Answer

Cause

ClickOnce cache

Resolution

  1. Close all Outlook windows
  2. Click Start button
  3. Search for %localappdata%\apps
  4. Delete folder named 2.0
  5. Install the plug-in

Additional Information

Note: You may need to show hidden files and folders in order to view and delete this folder.