Unable to unmount Exchange 2007 mailbox store database – Error code: MapiExceptionBusy: Unable to unmount database
Today I had an Exchange 2007 server with some problems. Some users were ok, others weren’t. There were various errors in the eventlog about activesync so I did an IISreset. There were some other errors about the Exchange Transport Service so I restarted that but as more reports came in from the users it became clear this was a mailbox store problem.
When trying to dismount the mailbox stores to do a clean restart of the Information Store service I was getting the error: Error code: MapiExceptionBusy: Unable to unmount database. (hr=0x8004010b, ec=-2147221237)
The mailbox databases had suffered from corruption in the past and had to be repaired so forcibly killing the Information Store service wasn’t an option.
Lots of Googling suggested the System Attendant service wasn’t running. It was, but I restarted it anyway. No joy, still the same when trying to dismount the store.
Then after a bit more Googling I came across this blog post from Luke Darby. It turns out the stores were dismounting, just very slowly and Exchange wasn’t being helpful enough to say so in the logs. The message is pretty much identical in the opposite case of being unable to start the store.
Checking the contents of the log directory showed that surely enough the logs were being replayed onto the database and after a few minutes all the stores dismounted. One restart of the Information Store service later and I had a working Exchange Server and (slightly) happier users.
Thank you Luke!
Hopefully both posts combined will help out a few more people.