Hi, we have recently deployed Exchange Server 2007 in our environment and have noticed a problem with Mailbox sizes.... We are using Outlook in Cached mode and some users have been clearing out their mailboxes to bring them down under the Mailbox size limit, but thesize changes are not being updated on the server For exampleone of our users had a MBX size of 347Mb which they cleared out 2 days ago and got down to 60Mb, if I look attheirfolder size on their Outlook client the 'Local Data' tab shows the size as 60Mb but the 'Server Data' tab still shows at 347Mb. Also when I check the properties for their MBX onExchange Management Console it shows the size as 347MB So it seems that the changes they are making are not being updated on the server i thought that there might just have been some delay so I left it for 2 days but nothing has changed so it seems there is a problem This is now affecting a number of our users Any help with this would be greatlty appreciated Regards Mike Dower - Systems Admin

Does running the Get-MailboxStatistics cmdlet with the -TotalItemSize parameter also show the same results?

Yes it does return the same results...... Mike

It sounds to me like there is a cached mode issue, perhaps with the OST, or perhaps the information is not synching correctly (I assume new email arrives ok?). I'd be tempted to backup the mailbox first, then take the client out of cached mode, delete the OST, and re-create via cached mode again. Then see what the various figures say. I typically trust the server size.

I would be inclined to agree with you if this had just affected one user, but this has happened to a number of our users (5 that i'm aware of) which makes me think this is a server side issue.... If I was to follow the steps you suggested does that mean that the work these users have done to clear out their mailboxes will be lost - i.e. will all the emails they deleted re-appear in their Mailboxes? Mike

Hmmm...interesting. What do they see if they use OWA? i.e. are messages that they've deleted from Outlook in cached mode still visible from OWA? If so, then clearly things aren't synching and they may find that they will have to delete things again. Also, are these 5 people using exactly the same build of Outlook as everyone else? It wouldn't be the first time that an Office SP or hotfix cured a few issues. In fact, there was a hotfix to cure Outlook 2007 PST/OST performance issues a while ago...

In fact, what version of Outlook are your users running?

Can you see if maintenance is completing without problems? If not, force it and see if it fixes the problem.