Mailbox Move error:Couldn't switch the mailbox into Sync Source mode

I've been working on a project to import PST files for quite some time. Some users we've helped have had many PST files and some had very large files.

One of our Archive Mailbox databases became very large for our tastes, so we decided it was time to trim all these databases down to 100G each from 380G each. Our main issue with the size was a place to restore. The time it takes to restore the database wasn't a problem, these were archived messages and the SLA was a full day. The problem was the 400G chunk of free space needed to do the restore. That was hard to find.

So as we moved archive mailboxes, I came across this error from time to time. The first time I saw this error, we were dealing with a user's mailbox that had over 22,000 folders. So I just exported her archive mailbox into several pieces and then imported it into another database. I just assumed that was a one time issue, and just moved on to my next task.

Then it happened again. This time is was on an archive mailbox 35G in size. I started searching on the error and found very little. Here's the error:

==============================================================

FailureCode                      : -2146233088

FailureType                      : SourceMailboxAlreadyBeingMovedTransientException

FailureSide                      : Source

Message                          : Error: Couldn't switch the mailbox into Sync Source mode.

                                   This could be because of one of the following reasons:

                                     Another administrator is currently moving the mailbox.

                                     The mailbox is locked.

                                     The Microsoft Exchange Mailbox Replication service (MRS) doesn't have the correct

                                   permissions.

                                     Network errors are preventing MRS from cleanly closing its session with the Mailbo

                                   x server. If this is the case, MRS may continue to encounter this error for up to 2

                                   hours - this duration is controlled by the TCP KeepAlive settings on the Mailbox ser

                                   ver.

                                   Wait for the mailbox to be released before attempting to move this mailbox again.

FailureTimestamp                 : 9/15/2012 6:24:00 PM

FailureContext                   : --------

                                   Operation: IMailbox.SetInTransitStatus

                                   OperationSide: Source

                                   Archive ()

                                   Status: SyncSource

==============================================================

I finally called Microsoft Support who said "This is a very common issue. Here's what you need to do... Change the TCP KeepAliveTime for the servers involved in the move. Source, Target, and CAS."

http://technet.microsoft.com/en-us/library/dd349797(v=WS.10).aspx

It turned out that I had to do that so much, I wrote a simple script to make the changes for me easily.

Get the code here: http://poshcode.org/3808