I have a problem with Exchange 2010 which is a nightmare for me. The problem is, that in Exchange management console i have several store databases in database management tab. only one is mounted, because i am using it. the second one is mounted, but it was used on other server before (now that server is dead). that database mounted status is UNKNOWN. The file of that database does not exist, but it still shows there. I can't remove it from management console, because it has mailboxes. i removed all mailboxes and disabled two arbitrary mailboxes. i can't delete it because i still have one arbitrary mailbox left. i can't move it, because it requires connection to dead server. i can't disable it, because i get error that it is the last one in organization.
Can somebody help me?

Solved it by using this command: Get-Mailbox -Arbitration -Database db1 | Remove-Mailbox -Arbitration -RemoveLastArbitrationMailboxAllowed

Now i have another problem. Exchange management console shows public folder from different server which is dead now. That folder was copied here, but it is not needed anymore. Public folder file has been deleted, and records from ADSI edit has been removed too. But i can't remove that folder from management console. i get an error Exchange isn't able to check for public folder replicas for "My Public Folder Database". Anybody can help me with that?