A couple of possible things to try:

(1) Reboot the computer, (don't open the program yet) and go to the "Start Menu" on Windows and do the "Repair Updates" for ProSeries.  Then open the program and try it again.

(2) E-file from Homebase, and when you e-file click the box to disable error checking.  Of course, before you do that you will want to double check that there aren't any legitimate errors or missing entries in the tax return.