>Sorry, Christof, I can't supply an example. But hopefully someone who has experienced this will read this and report theirs.

I have too many examples :) We had a large vfp5 app running without NOFILTER a year or more ago with many users. It mostly ran fine (as far as SQL, anyway) for the first month or so, but we started getting reports of errors and "funny" result sets in grids. I finally found that the crashes were occurring seemingly randomly on USE DBF() AGAIN on result set cursors. Almost all the time, we got fresh new physical result sets from SQL. But occasionally, vfp would decide to filter a table instead, and hence the errors.

We added NOFILTER everywhere where a problem could occur, and that resolved everything, of course.