Hello, on a mac I have the MAIL ( which comes with the mac ) software setup with Archive folders, when I drag the e-mails into the archive folders they move ok however the Exchange mailbox does not reflect the move and the quantity and size remain the same causing the mailbox to be very large.

Can you confirm using OWA ,. that you cannot see the archived mails in the archive folders.

Yes I can confirm that what else could be happening as unfortunately it is not Outlook this time and it is surely less familiar.