iTunes Add-in Breaks Outlook
Many people complain that every time they open Outlook, it says The data file ‘Mailbox – User Name’ was not closed properly. The file is being checked for problems. This often takes 10 to 15 minutes. In every case, the person swears that they did close Outlook properly. And in every case, the person has iTunes installed.
iTunes installs an Add-in in Outlook that prevents it from closing properly. As far as I know this is the only function of the add-in. It should be removed and Outlook will work normally again. While you are in there, look for other add-ins that you don’t need. Many programs needlessly install add-ins to Outlook.
Add-ins are shown in Tools-> Options-> tab Other-> button Advanced Options…-> button Add-In Manager or button COM Add-ins
Add-ins are shown in Tools, Trust Center, select Add-ins on the left and then click Go…