Thanks very much indeed for the suggestions, Peter. Sadly I had no joy
with these.

If in Word, you choose Tools / Mail Merge / Get Data then choose an
Access database as the datasource, it will open A2K. I reset the file
association, just in case, so if you click on the same MDB files in
Explorer it correctly uses A97. Word / merge still insists on A2K,
though. Aaargh!!!!

Unless I have (or receive!) any inspiration in the next couple of days
I'll just uninstall O'2K and re-establish the merge. I presume it will
then have to use O'97. Then I'll reinstall O2K again.

Sounds logical enough to me, but I'm really hoping to get to the bottom
of this...

Anyone else got any ideas?

Thanks again.