Hi,

After running several tests and trying different solutions, I came to the following conlusion:

- There is a related table in the grid. If I set a relation, the record in the related is locked. The funny thing is, the record in another related table does not get locked.
- If I use an expression for the related table (iif (seek ... etc.) then the record at first isn't locked, but after clicking on the column (this triggers some code, doing lookups in the same table under another alias) the problem reoccurs.
- The easiest way to check all this is to lock the record in the related table and then try to change the record.

Still one question left: if the users work in the app, once the record is in use message has appeared, it keeps appearing, no matter what related record you're on.

My solution is to not use an expression as the controlsource for the column instead, and in the click event change the value of the table. This gets rid of any thing the grid seems to do automatically. The only disadvantage is that I cannot use the checkbox, because it will still try to update its recordsource, and come up with a message "the control is read-only". Using a textbox seems to work fine though. Maybe I'll try using pictures lateron.

I'm still open for more information about this. I haven't got the feeling I completely understand this behaviour.

Auke