I finished up our migration to Server 2008r2/Exchange 2010 this weekend and despite some pesky little issues, it has gone well.
One which came up was a Send /Receive error in outlook- Error 0x8004010f. Object not found.
After hours of searching, it tuned out this was a common error with nearly as many different solutions for reported issues. I finally found out that my Offline address book setting was blank!
Ogranization Configuration-> Mailbox -> Database Management-> Mailbox Database->*Rightclick Properties->Client settings
I just set it to the default and bam!
This resolved all our send/receive errors.
Oh and if you want to increase the default datastore size for all the mail boxes,
Ogranization Configuration-> Mailbox -> Database Management-> Mailbox Database->*Rightclick Properties-Limits
Here you can change the default storage limits.