It's VFP9 bug and MS is aware of it.

>A collleague and I just uncovered a difference between vfp8 and vfp9 that we were not expecting.
>
>Running the code below in vfp8 will give you a sequence of _text values something like: -1, 15, 15, 15 while in vfp9 it will give: -1, 15, -1, -1.
>(where 15 is the file handle to the textmerge target file). Further tests show that vfp9 does indeed close the textmerge file. So, in short, vfp9 shuts down textmerge to file globally when it encounters an error in try/catch.
>
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