I am running Exchange 6.5 on Windows 2003 server. I am doing backups to tape using backup exec 9.1. I keep getting "cyclic redundancy errors" and "incorrect function" errors. I have 3 drives on my exchange server, one with the database, one with the install and one with the address book and logs etc. Two of the three drives keep giving me these errors. I've verified that the permissions are correct, the tapes and drive are working properly. It appears that the exchange db is the only thing that doesn't back up. Any thoughts?