Problem: When trying to backup my exchange 2010 server using Roxio Retrospect 7.7 I got the following error: “Sorry, can’t list volumes on Exchange mailboxes on exchangeserver. Error 3420 Unknown. When I would look at the volumes in the client portion of Retrospect, I got an can’t track volumes, error 3420(Unknown). All of this had to relate to me not being able to browse my Exchange mailboxes.
Solution: Found a document on Roxio’s site that let me know what needed to be done to backup Exchange 2010. Looks like the MAPI client libraries weren’t installed on my server. I had to go to download the the MAPI files and install then onto my server. I then removed the client and re-authorized/licensed it in the Retrospect program. Problem Solved.
Roxio’s knowledgebase article on how to setup Retrospect for Exchange 2010.