Thanks a lot, Sorin, for your pointers. The first document is indeed our own document (for our products) and the other link is also helpful. It does indeed look like the memory leak may come from that ctSchedule.ocx.

>As I see it, the c0000005 exception code is confirming the memory leak caused by ctSchedule.ocx
>There is an older (2009) document here that may be reporting on this, especially the following, don't know if it applies to your app:
>From http://portal.siriusware.com/docs/kb-pdf/error_and_other_messages/sysmanager_reportmanager_2009_apr_16.pdf
>
>CAUSE: Receive error after repeatedly running the chart view of the Consolidated or Individual Instructor Calendar reports.
>FIX: This appears to be a memory leak in the 3rd party schedule control. This will hopefully be fixed in an upcoming version
>
>Also from Nov 2009, a DBI Tech Tip suggest that c0000005 errors may be caused by UAC issues.
>http://www.dbi-tech.com/TechTips.aspx