When faced with a problem such as this, it is often useful to point Quik Reports for Windows, or Crystal Reports for Adagio at the data and try and isolate the records in the history that are causing the problem. Neither of these products will crash when confronted by a ridiculously large number (as the Windowing System Manager will). Once you have isolated the bad record(s), a simple disk editor such as Norton can usually be used to fix the records.