>I have a Form class in which are two tables loaded (PARENTTABLE and CHILDTABLE).
>
>PARENTTABLE and CHILDTABLE are linked with CID_PARENT field in PARENTTABLE.
>
>When I want to do:
>
>SELECT childtable
>APPEND BLANK
>
>VFP 8.0 shows:
>Cannot write to the record because it is in use (Error 1502).
>
>I don't understand why?
>
>I have discovered that when in DataEnvironment I delete Relation object between those two tables error disapear, but I need that Relation.

Do you have a referential integrity trigger on the child table for the foreign key? If so, could use INSERT - SQL and do something like:

INSERT INTO ChildTable (ParentID) VALUES (ParentTable.ParentID)