Exchange Mailbox growing rapidly

We have a mailbox that in the past month has grown from >2gb to over 33gb.  The number of total items in the mailbox has grown normally.  It seems like one day a week the mailbox size increases and I get multiple transaction logs per minute. Looking at the mailbox I'm not finding large emails that would account for this size mailbox.

I've scanned for viruses and found nothing.  I also archived older emails which reduced the number of items in the mailbox but the size only shrank about 500mb.

Any ideas on what could be causing this mailbox to grow?
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jwspeakerAuthor Commented:
Apparently, there was 30+gb in the Sync Issues Conflicts Folder.  I think that was because 2 users use that mailbox and 1 had Cache Mode enabled and the other had it turned off.  I turned Cache Mode off on the user that had it on and cleared out the conflicts.  After I did that the mailbox shrunk down to the 400mb it was before.
Thomas GrassiSystems AdministratorCommented:
What about attachments?

I had many users receive serveral attachments

We had to instruct them to detach the attachment from the email.

Just a thought
Manpreet SIngh KhatraSolutions Architect, Project LeadCommented:
Hope user didnt move some PST folder to Mailbox moving it so high and if you have some limit on the Mailbox for Send\receive how is it working ?

Can you please share some screenshot

- Rancy
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What versions of exchange /server o/s ?

Does the user have cached exchange mode if so is it the OST ( What size is it)

See if this helps

I have narrowed it down to a particular user. EXMON shows that this user is generating 50MB of log every minute.  There is nothing in the queues during this time though.  She also doesn't have any messages stuck in her outbox, and no large messages in her mailbox or archive folders.  It doesn't stop when she closes outlook but does stop when she logs off of her computer.  Logging back in and using Outlook doesn't appear to start it up again though.  I have installed wireshark and the traffic causing the problem is DCERPC traffic.  Looks like the client is requesting something and Exchange responds but it isn't clear as to what it is requesting.  I am going to rebuild her PC and upgrade her to Windows 7 and Office 2010.  She was on XP and Office 2003 before.  If this doesn't work I'm going to delete her AD account and mailbox.  Hopefully this will be enough.  I am also going to move her mailbox to a seperate database on a seperate volume so that it can't impact the rest of the organization.   I will also migrate all the other mailboxes to a new database just to ensure that everything is clean, and back to the size that it should be.
If anyone can explain what could have caused this, and why the database has grown from these DCERPC requests when the user is doing nothing with Outlook, I would be very interested.
In case anyone is curious, the details of the frames shown in wireshark look like this:
From Client to Exchange Server:
Request: call_id: 207918 opnum: 11 ctx_id:0
From Server back to client:
Response: call_id: 207918 opnum: 11 ctx_id:0
The numbers just keep incrementing and about 200 of these get generated every second.


Tuesday, March 22, 2011 10:57 PM


0 Points



I have rebuilt the user's machine, and so far the Exchange activity has gone back down to normal.    Not sure what was wrong with her PC but the issue is now resolved. I am migrating the mailboxes to a new database to bring the size back down to what it was before this issue started.
drop the mailbox and associate her/his account with a new mailbox.  If the problem is with a single mailbox, you can then import what you need back.
Manpreet SIngh KhatraSolutions Architect, Project LeadCommented:
Thats good but strange as this should be available in Outlook folder size data ..... and i have never seen Conflicts folder with even in MB's

- Rancy
What was causing it - so we can all learn something ?
jwspeakerAuthor Commented:
Because I figured it out on my own after I got none of the solutions to work.
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