Link to home
Start Free TrialLog in
Avatar of denver218
denver218Flag for United States of America

asked on

Moving a 23GB Mailbox from Exchange 2003 to Exchange 2010

I am doing an exchange migration for a client and ran into a little surprise.  I moved all mailboxes from exchange 2003 to the exchange 2010 server, but one, which is a 23GB mailbox.  My question is has anyone ever moved a mailbox this size from exchange 2003 to exchange 2010?  Will it move successfully?  I haven't attempted to move it yet.  Any advice would be greatly appreciated.  Thanks.
Avatar of Auric1983
Flag of Canada image

With such a large mailbox you might run in to a lot more corrupt messages than with a small mailbox, so you may have to set your threshold for corrupt messages higher.  

That being said, if you have a good backup there is no harm in trying, worst case the move fails and the mbx stays on the 2003 server?

Exmerge is out unfortunately as it's limited to a 2gb PST file.  The only other way I could think to move a mailbox of this size is by opening the mailbox in outlook and doing a File > Export to a unicode PST file.  

Avatar of Glen Knight
Exmerge can filter the mailbox if required but it shouldn't be needed.

I have moved mailboxes larger than that without any problems, I would suggest doing it over a weekend though.
yes go ahead and move the mailbox
Unicode format supports max 20GB PST. I would suggest you to export mulitple PST in 2GB size. Export them Folder wise. Once all data is exported out. Delete that from the user mailbox. This will reduce the mailbox size. Then move the mailbox, later import all PST. Safe and secure method.
Avatar of Glen Knight
Glen Knight
Flag of United Kingdom of Great Britain and Northern Ireland image

Link to home
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
In what way, Data can be lost. I am doing it from last 8 years.
Avatar of denver218


Thanks.  I really don't want to go the PST route if possible.  demazter, you said above you have moved mailboxes that were bigger than 23GB successfully in the past to exchange 2010 correct?  I think I will take that approach and start the move this evening and let it go into the weekend.
Yes I moved mailboxes that size and bigger without problems.

>>>In what way, Data can be lost. I am doing it from last 8 years.

Then you really need to re-think your migration strategy.  I specialise in Exchange migrations and have never had to export to PST.

The use of PST files can cause dataloss because on a mailbox that size you would have to do around 15 passes using emerge to get all the data out. If you don't get it right you will lose data.  You are also exporting to different storage away from exchange, another potential data loss.
Thanks for your suggestion