Oversimplified :-) to the extent of losing contents ...

>To simplify Ed's reply (bg), both forms are using the Default datasession, most likely. Meaning, if one form closes the tables, the other form can't find them anymore. You can set AutoCloseTables to False (.F.) in one of the Forms to resolve this, but the true resolution depends on the relationship (parent,child) between the Forms, if any.
>
>
>>I have a form with 2 tables
>>if I open a second form over it, when I get back
>>to the first form, is not possible to find the tables.
>>
>>I think this is not the right way to do.
>>
>>What the right way to open a form over other form?
>>
>>I heard about child form. How that works?