memory access violation on replay. web http/html protocol for sharepoint app


I have a recorded jus the login page of sharepoint application.  It seems that there was only a 'securitytoken' to correlate.  I saw 2 cookies, jession id and another one that exist in recording but also in replay.  They seem to correct on replay without correlation (they get added in the background and are not hard-coded in the script.
Eventually on replay, I am getting a memory access violation.  I have compared the requests and reponses leading up to the step that fails and have not seen any reason to believe that something is missing in the script.  All responses were correct.  Also, when comparing the response of the step that fails I don't see anything that would suggest why this error occurs.

Any ideas?