User Michael wanted to reset the mailboxes he had selected for archiving.
Of course, you can get the big hammer out and use Prefs Editor.
If you want something less destructive then there is a small checkbox in the Mailbox selection of the Email Info part of the Setup. Click the checkbox once to select all visible mailbox. Click the checkbox again to deselect everything.
Do this for every active email client and your IMAP accounts and you have reset your archiving selection.