Greetings Erik
>
>Do you get this error with an empty copy of the table?

I do indeed...

>Or is there a particular piece of data causing it? If it happens when empty, you could e-mail me the table if you want, and I'll see if anything unusual makes itself obvious to me.
>

I may well take you up on that kind offer. But you've given me an idea which I'll check out and report back on first...

Ciao

Harry