http://technet.microsoft.com/en-us/library/aa998863(v=exchg.80).aspx
If you are at the end of Migration. Check there are no user active on the DB:
Show all mailboxes on Database "mb3"
Get-Mailbox -Database "mb3" | select Displayname, Alias, Database, OrganizationalUnit | ft -wrap –auto
Also check this KB for hidden accounts and dead accounts :
http://www.butsch.ch/post/Exchange-20072010-Delete-default-Mailbox-Database-remove-last-MailboxSG.aspx
Get the Path of the DB:
How to copy the actual path without moving it:
PATH OF OUR DB: D:\sg3\mailbox\mb3.edb
Cancel
Make sure you have enough space to defrag the Exchange DB
Check if you can DEFRAG LOCAL (Need same space or over a temporary network location or SAN Storage).
DB = 67GB / Free Space on D: Drive = 310GB / OK can be done localy
/T = Temporary Drive to Defrag
Eseutil.exe /D D:\sg3\mailbox\mb3.edb /t d:\temp_mb3.edb
Check where your Exchange runs:
Path: D:\Program Files\Microsoft\Exchange Server\Bin
Got to that path in a DOS Command.
DO NOT use Quotation Marks = "D:\sg3\mailbox\mb3.edb"
RUN THE DEFRAG on the OFFLINE DB.
eseutil.exe /d D:\sg3\mailbox\mb3.edb /t d:\temp\temp_mb3.edb
DEFRAG with Temporary Drive d: because it has enough space!
65GB > 169MB (Because MOVED Users to Exchange 2010 Before)
Take the DB Online