Hans-

>the form I use to call the report is based on a base form (= a class created by someone else). The program code which calls the report is in this base form. I looked at the code but I don't see any "go top" instruction or anything else that could cause the recordpointer to go to the first record. I will have a look with my boss (he wrote the base form) to see if I haven't been missing something.

Have you put a breakpoint on the line of code that does the report, and checked that at that point the record pointer is where you think it should be?