I need to bring the email system completely down as they are going to do some wiring in the room. I can do a full backup the day before but I do not have enough time to do a full backup on the night where work is being done. Backing up the entire exchange server takes 5 hours and then another 1:40 for cataloging. Should/can i do a differential or incremental backup on the exchange 2010 server using Backup exec 15?