When I back up my MSS Shared Folders to an external hard drive the Mac folder that contains the Time Machine backups does not seem to back up incrementally. It appears to backup a complete new volume each time. My MSS is an EX470 with the Mac backup software.

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HP MSS EX470 & Ex490, iMac 24" & 13" MacBook, Think Pad T61 with Win 7 Professional, Dell 4600 with Win XP Professional

The reason for this is that the Mac backup is one single large file. Regular backup software will see the new timestamp on the file from when Time Machine runs and think that the entire file has changed and needs to be backed up in its entirety.

You need backup software that supports block level incremental backup in which only the individual blocks that have changed in the file are backed up when the file is touched or modified.

Jungle Disc can do this but I'm not sure of other software that can.

The best thing for you to do is exclude the Mac share from automatic backups.