Did you check to see if the database is marked include in your project file. If the database file is marked included some time it does cause the problem.

>As anybody got this weird problem: when opening a form (via a DO FORM or
>MODIFY FORM), if the database is open, VFP generate a "File access
>denied" error and won't load the form.
>
>The only solution I found, is to remove the database from the project,
>pack the project and add the database again.
>
>I searched the KB without any success.