Outlook Add-ins can have adverse effect on the Insight Connector.
Because the Insight Connector was developed to function as closely to a MAPI client as possible, other Outlook add-ins can interfere with the operation of the Connector with Outlook.
Scenario: A user explained that every time he tried to open any email, it would cause Outlook to crash. As a part of normal trouble-shooting, it was suggested that he disable the mail scanning portion of his anti-virus software.
Using the software GUI, the user disabled mail scanning but Outlook continued to crash. Inspection of the Outlook add-ins revealed that the anti-virus add-in was still enabled even though the user disabled it in the GUI. Once this add-in was disabled, Outlook performed without crashing.
To verify what Outlook 3rd party add-ins you may have installed see below: Outlook 2003:Tools > Options > Other > Advanced Options > Add-in Manager Outlook 2007:Tools > Trust Center > Add-ins