Exchange 2010 – MapiExceptionTooManyMountedDatabases

During a restore I was facing the following error so why not to mention it here.

Couldn't mount the database that you specified. Specified database: RDB2; Error code: An Active Manager operation failed. Error The database action f
ailed. Error: Operation failed with message: MapiExceptionTooManyMountedDatabases: Unable to mount database. (hr=0x8004060e, ec=-2147219954)

I already had an one recovery database mounted on server and it is reason for the error. Why? Because each Exchange 2010 or Exchange 2013 server allows for only one recovery database to be mounted at a time. The server can contain as many recovered databases as disk space allows, but only one can be mounted as the recovery database. The database mounted as the recovery database is counted in the maximum number of databases that can be mounted at a time. A recovered database mounted as a server’s recovery database is not associated with the original mailbox in any way (more).

Additionally, here is my procedure of the restore:

  1. New-MailboxDatabase -Recovery -Name RDB2 -Server EX2010 -EDBFilePath R:\RDB2\DB\RDB2.edb -LogFolderPath R:\RDB2\Logs
  2. Get-MailboxDatabase -Status| ft name, mounted, Recovery -a
  3. Backup Exec restore process (data restored into RDB, the database is mounted automatically)
  4. Get-MailboxDatabase RDB | Get-MailboxStatistics | ? {$_.DisplayName -like “*Pepa Novak*”}|fl
  5. New-MailboxRestoreRequest -name “Restore210613” -TargetMailbox kasajfilip -SourceDatabase “RDB2” -SourceStoreMailbox “Personal Archive – Pepa Novak” -BadItemLimit 100 -AllowLegacyDNMismatch -AcceptLargeDataLoss -targetrootfolder “Restore210613”
  6. Get-MailboxRestoreRequest -name Restore210613 | Get-MailboxRestoreRequestStatistics | fl
  7. New-MailboxExportRequest -name “Export210613” -Mailbox kasajfil -Include FoldersRestore210613/* -FilePath \\EX2010A\PSTfiles\PepaNovak(arch).pst
  8. Remove-MailboxDatabase RDB2
  9. Manually removing the database file