>It occurs when I Modify the form.
>
>I am not using any classes except what is included in VFP, and I have not modified any of them.
>
>I actually searched every memo field the way you indicated and found nothing.
>
>The form runs fine, but that may be just because I haven't hit the error yet.
>
>???

It could be trying to evaluate a relative path that it can't find.

e.g. say form was in one directory and data was in another
then one or the other was moved

Form directory             c:\root\sub1\myforms
Data directory             c:\root\sub1\mydata
Relative form to data      ..\mydata

Form moved to              c:\root\sub2\myforms

Relative path              ..\mydata
   tries to resolve to     c:\root\sub2\mydata

If c:\root\sub2\mydata directory doesn't exist this could be the problem.