> I have two tables: a loockup dataset"ProductType" and a keysource
> dataset "Product". I have a form to manage the records of the
> ProductType dataset. When I scrool this table, I have the error
> described before. The other parts of program are working fine (the
> loockupcombobox is ok).

Are you trying to share a dataset between a lookupcombo and a separate
form used to manage records in the lookup table ??? You cannot do
that! You must have a one dataset (TIB_Query or whatever) for the
lookupcombo and another separate dataset for the form used to insert
records into the lookup "ProductType" table. After you have done an
insert refresh the dataset attached to the lookupcombo so that it will
see the new record.

hth

--
Geoff Worboys
Telesis Computing