If you ever get this message.....
Error 998 , Failed to retrieve error message from print engine.
We found this whilst doing a crystal report that was running against an oracle database.
The cause was that a VIEW had been created for use with the report. Whilst designing the report, the queries worked, when running the report, it was being called by a different database user which didn't have permission for the report.
This was solved by granting the permission to access the table within oracle.
Hope that helps