"USE [ViewName]" opens a View. When you do REQUERY() VFP compares record structure with previous and generate error "View definition changed" if they don't match. That's why error is generated only in the second case. You can find out which view fields cause the problem by
1. Set parameter values to ones that don't cause an error
USE [ViewName]"
LIST STRUCTURE TO PRINTER or FILE
2. Do the same for parameters values that cause an error
3. Compare structure of both views as reported by LIST STRUCTURE command.

>Hi Sergey,
>I've verified that there is data for the dates involved. I've also verified that the view works if there is no data for the dates involved.
>
>The view is very long, 117 fields including , 6 udfs() that do there own Select(), 4 tables involved (only 1 updatable).
>
>I have discovered something else. And I'm pretty sure that it's not the data involved.
>
>It only happens on REQUERY(). If I "USE [ViewName]", it works fine, but if I then REQUERY() it crashes. Naturally it crashes in my form, because I always start with NODATA then REQUERY() when I need it. If I can't figure out what is happening, I'll change my REQUERY() to USE in my grid (can't say I like that idea).
>
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