Unable to disable the Add-in in Outlook 2010

Question

I am developing a vsto COM Add-in with form region for Outlook. It works fine. However, I am facing problems disabling the Add-in in Outlook 2010.

From the File Menu > Options > Add-ins > COM Addins (dropdown) , I am unchecking my Add-in. But when I restart Outlook, the add-in is enabled again. If I check in the COM Addins list, its again enabled. Even the registry entries indicate that the Add-in is enabled again. Does anyone know what might have caused this? Can enabling and disabling be handled in my code, or will it be taken care by Outlook itself.?

Answer 1

If the addin is installed in both HKCU and HKLM, make sure you disable it in the HKLM registry hive.

Answer 2

Typically when any changes made in the host application run under regular user privileges are written to the HKCU hive. For example, if the add-in is registed in the HKLM hive any changes in the UI are written to the HKCU hive due to the fact that the host application was not launched with admin privileges (which is required for writing to the HKLM hive). See Registry Entries for Application-Level Add-Ins for more information.

P.S. Try to run Outlook with admin privileges and see the difference.

Answer 3

As it turns out, its is a bug in Office 2010 Professional. To disable the add-in, you need to run Outlook as an admin, and then disable the add-in.