An issue with mail merges may arise when IIS autologin is enabled.
The following error message is displayed in the Sage CRM logs:
"User with a username xxxx not found in CRM"
"User not logged"
This issue is caused by Tomcat attempting to check for an active user session, and the user's Windows password not matching the password in the database.
Work around / Resolution:
Blanking the user's password from within CRM resolves the issue.
This issue is fixed in v7.2b.