Due to an error in the DVM (bug 19054), errors in GRE currently cannot be trapped in the 4GL program. We hope to fix the issue for the 2.31 maintenance release. What you can do is to redirect standard error to a log file to find out what kind of errors are causing the problem. To do that you have to modify the file gre/bin/greportwriter and apend a " 2>>/tmp/grelogfile.txt" to the last line. Be sure to redirect stderr only. as redirecting stdout will cause all reports to fail.