Have and Interchange that will keep messages in the boxes and never deletes them. I ran defrag, deleted and added back one of the problem mailboxes.
Seems to be a recurring problem. Is there a way to prompt a cleanup.

You probably have database corruption. You should be able to run the utility for removing the corruption, once you stop VM services, of course, and then reboot.

Which utility is that?

That's kind of the answer I thought you might give. At this point I would recommend contacting a dealer in your area who can provide you with the necessary support (possibly for a fee), who has access to the necessary tech support, documentation, experience, etc. If you need help finding one, check out the Installers link at the top of the page, or send me a PM, as I know of at least one dealer in your area.

Does anyone know the program name by chance?

I see on your website that you handle Key Voice. Just give tech support a call. Since this is your first time with this utility they will give you the documents on this no problem.