Hello, We're planning a mail migration to Exchange 2010. Avg. mailbox sizes ar 1 GB. I'm trying to determine how much total WAN bandwidth will be required for post migration .OST download. For example, My remote office has a 3 Mb MPLS link to the Exchange servers and I have 500 migrated users with 1000 MB mailboxes. When all those users show up the next morning and log in, they'll all be downloading their .OST file at the same time and saturating the WAN link (500 MB of OST download). I'm looking for a WAN throttling policy or a best practice for how this problem is best handled. Staggering migrations is not really an option and I have limited bandwidth increasing potential. Thanks

Honestly, I wouldn't worry about it. Cached mode synchronization is designed to be gentle to the network. If you're really worried, spread out the user migrations over several days.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Honestly, I wouldn't worry about it. Cached mode synchronization is designed to be gentle to the network. If you're really worried, spread out the user migrations over several days.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

When I've done those migrations when there are worries on the initial load, either it's hardware, network or what ever.. Configure so that x users uses cached mode Day 1, then add x users Day 2 and so on Or just inform them during Day 1 there can be some delay's, mostly likely they won't have anything against it since they know Jonas Andersson | Microsoft Community Contributor Award 2011 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82