archival calculation


Hey folks, I have a client who is on Exchange Server 2013, has 9TB of active mailboxes that are backed up. There is no archiving in place.

As part of their move to Exchange Online they will be implementing 4 year and 8 year archive policies (depending on role), and as such their backup requirements will be shrinking.

Because they must have backups (for legislative purposes, regardless how great the hold & retention features are), they are trying to estimate how big their active mailbox sizes will be after the archiving is implemented - so that they can get accurate quotes for cloud backup providers.


Does anyone have a script that might be of use for this?

1 Reply

You will have to use some EWS-based script to enumerate all items older than a given date and report on the size. Glen has an example one here:


Another one from Michael: