Quest.MigrationManager.Exchange.MMExException: No objects were returned from the configuration database. (4338468)

When trying to set a target mailbox database for a collection the following pop up error will be displayed:

"No objects were returned from the configuration database."

Additionally the MMEX console log (EMWMigration.log) will contain the following error:

Error MMExOperations|Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.ThrowException\tError: Exception: 

Quest.MigrationManager.Exchange.MMExException: No objects were returned from the configuration database.

   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.ThrowException[TRetVal]()
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.<>c__DisplayClass1`1.b__0(SqlDataReader reader)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.InternalExecuteCommand(String commandName, FillCommandParametersDelegate fillParametersFunc, Action`1 ExecuteReader)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.ExecuteCommand[TRetVal](String commandName, FillCommandParametersDelegate fillParametersFunc, TreatResultDelegate`1 treatResultFunc, TreatMissingResults`1 treatMissingFunc)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.ExecuteCommand[TRetVal](String commandName, FillCommandParametersDelegate fillParametersFunc, TreatResultDelegate`1 treatResultFunc)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.GetExchangeServer(Int32 serverID)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.GetValueAndAdd[T](IDictionary`2 dic, Nullable`1 id, Func`2 getFunc)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.CreateMailboxDatabase(SqlDataReader reader, IDictionary`2 dicServers, IDictionary`2 dicStorageGroup)
   at Dell.MigrationManagerForExchange.API.StorageMailboxDatabase.b__8(SqlDataReader r)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.<>c__DisplayClass1`1.b__0(SqlDataReader reader)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.InternalExecuteCommand(String commandName, FillCommandParametersDelegate fillParametersFunc, Action`1 ExecuteReader)
   at Quest.MigrationManager.Exchange.Basis.ConsoleDBLayer.ExecuteCommand[TRetVal](String commandName, FillCommandParametersDelegate fillParametersFunc, TreatResultDelegate`1 treatResultFunc, TreatMissingResults`1 treatMissingFunc)
   at Dell.MigrationManagerForExchange.API.StorageMailboxDatabase.GetMailboxDatabaseDisplayName(IMailboxDatabase mdb)
   at Quest.MigrationManager.Exchange.View.Controls.TargetMDBControl.UpdateTargetDBName()
   at Quest.MigrationManager.Exchange.View.Controls.TargetMDBControl.set_MailboxDatabase(IMailboxDatabase value)
   at Quest.MigrationManager.Exchange.View.PspSelectTargetMDB.OnSelectDatabase(IExchangeOrganization targetOrganization, ISelectTargetMDBPageControl control)

Additionally, the Collection Management Utility can't import any collections, due to this issue.

This can occur when a mailbox database and the server or DAG that owns it, is deleted and then recreated with the same names.  When this happens, the EXCH_MAILBOXDB table will contain 2 entries for the mailbox database.  The first and older record will have the "Deleted" column set to 1 and the newer record will be the correct value that should be used and is set to 0.

The stored procedure GET_EXCH_MAILBOXDB_BY_DN doesn't check if the mailbox database has been deleted and can return a deleted mailbox database that points to a deleted Exchange server ID (this is a defect).

The MMEX console then queries SQL using another stored procedure (GET_EXCH_SERVER) for the Exchange server that owns the mailbox database, using the Exchange server ID returned by GET_EXCH_MAILBOXDB_BY_DN.  This then runs a SQL function called F_GET_ALL_EXCH_SERVER which only returns servers which have NOT been deleted.  Since the server ID returned by GET_EXCH_MAILBOXDB_BY_DN points to a deleted server it means that nothing is returned to the MMEX console thereby causing the "No objects were returned from the configuration database." error.

Waiting for a fix in a future version of Migration Manager for Exchange

WORKAROUND

Modify the query used by the GET_EXCH_MAILBOXDB_BY_DN stored procedure to include a check for deleted mailbox databases, by changing the following line from this:

SELECT * FROM EXCH_MAILBOXDB WHERE UPPER(DN) = UPPER(@DN)

To this:
SELECT * FROM EXCH_MAILBOXDB WHERE UPPER(DN) = UPPER(@DN) AND DELETED = 0

To modify a stored procedure.

1. Logon to the SQL Database by using SQL Server Management Studio.

2. Expand out your MMEX Project Database > Programmability > Stored Procedures.

3. Find the dbo.GET_EXCH_MAILBOXDB_BY_DN table, right click and chose "Modify".

4. Find the top line from above and replace it with the bottom line from above.

5. Hit the "Execute" button to save it.