Another ADO run-time error!!!

Hello!

After many hours I declare my defeated.

I've got a MDI form and 2 child windows: inside an ADODC control connected to the same table (in the first window used for a datagrid, in the second window used for data entry and updating). The table is inside a Access 97 MDB with a ODBC DSN connection. Important! The table contains a great quantity of records (20000) and I don't want to requery or refresh: it takes too much time and I need speed! When I update one field in the second window and I use the resync method, the updated information appears but when I make the resync in the first window I receive the following (deadly) error message:

run-time error '-2147467259 (80004005)':
informations on key column are not sufficient to make the update

(sorry, but this is my translation from italian version of error message)

When I decided to port my old clipper program in vb6 professional and using ADO I embarked me on an mission impossible (3).
Thanks a lot for your kindness.

MAX