They looked up support cases with the same bucket id and only found one match - that customer had other problems (including BCM was misconfigured) and they don't know for sure which one caused the shipassert alert. If you have BCM or Business Connectivity Services addin, they recommend starting with them.
They don't have a 'smoking gun' for the error, so the standard troubleshooting advice applies - disable addins, try Safe mode etc. If that fails, open a support incident for more indepth investigation.
I know Adobe Reader and Symantec's varios security software have been blamed for this error too. I believe its related to net framework, so I'd look at programs that use net framework and interact on some level with Outlook (ie, Reader provides the PDF preview for the reading pane, symantec's norton AV scans email for viruses). BCM uses net framework too.