Not executing a IsNull scenario when writing a new record

[NeoPa]

I wouldn't even entertain the idea that it was done for any reason other than your temporarily losing the plot in an inattentive moment. This happens to us all from time-to-time.

I would just offer an alternative for your first line. Some don't like using the Nz() function, but otherwise it's a more compact version.

If Nz(Me.ProductIDFK, 0) = 0 Then

[kcdoell]

Here is a stretch! Since [ProductIDFK] is a LONG INTEGER Field bound to [ProductID], by Default (unless otherwise changed by you), it will have a Default Value of 0 for any given New Record and will pass the IsNull() validation. Either check the Default Value Property of the [ProductIDFK] Field to make sure it is not set to 0, or add the following Validation Code:
[CODE=vb]
If IsNull(Me![ProductIDFK]) Or Me![ProductIDFK] = 0 Then
Msgbox "Missing Blah, Blah, Blah..."
Cancel = True
Exit Sub
...[/CODE]

Let me know how you make out.

The reason why it was happening makes complete sense to me now. In fact, Yesterday I said to myself that that somehow the DB did believe that there was a value being slected in [ProductIDFK]; it was the only thing that made sense to why it was happening.

Both solutions solved the problem.

Thanks a lot!!!

Keith.