The profile could not be saved due the following issues: Invalid Mappings found

Hi all,

I am currently evaluating Binary Tree Directory Sync Pro for Active Directory for a major INTRA-ORG migration. I have set all mappings between the attributes to default values. I can also save the profile and validate it successfully. However, when I try to activate the profile, I get the following error: "The profile could not be saved due the following issues: Invalid mappings found". A reset to standard mapping or re-reading the schema etc. has unfortunately not helped. I'm slowly running out of ideas. No errors are logged in the log files.

Help would be really nice.

Best regards
Joern