It sounds like you're closing tables manually, and you're doing it too soon. If you close the controlsource of objects before the objects are destroyed, then you'll get this error. You need to do it from the form's Destroy method instead. I use this code in the Destroy of my form class:

IF This.DataEnvironment.AutoCloseTables = .F.
   CLOSE DATABASES ALL
ENDIF

>Hello all
>
>When i close a form with thisform.release i get a error message cannot access the selected table.
>
>what's the cause for this error
>
>txs