I'm using Microsoft Outlook 2007 in a Windows 7 environment. I wanted to delete one of the ad-ins and followed the Microsoft Outlook Help as far as how to do so. Their instructions were:
1-On the Tools menu, click Trust Center, and then click Add-ins.
2-In the Add-ins box, identify the add-in that you want to enable or disable and note the Add-in type located in the Type column.
3-Select the Add-in type in the Manage box and then click Go.
4-Select or clear the check box for the Add-in that you want enable or disable and then click OK.
After following the directions, I received the error message shown on the screenshot which indicated that I needed to have administrative privileges to make the change. unfortunately, I cannot figure out how to sign into Outlook as the administrator.