Hi,

you need to specify the database including the storage group. For instance:

Storage-Group Name: SG1
Mailboxdatabase Name: MB1

Path you need to use: SG1\MB1

Hi,

I understand you want to migrate the mailbox from 2013 to 2007.

Can you share your command of moving mailbox?

According to the error, it indicated that there is a mailbox database named ddb2 on your server 2007.

Please check if you can find DDB2 database on your server 2007 and you can try to rename it.

Best Regards,

David 

using the GUI on the ex2013 server to move the mailbox. will try using powershell.

Hi,

Is there another database on another server called DDB2? And I'm guessing that the current mailbox reside on the same database name, called DDB2? I would suggest to create another database with a different name.

Hi,

Correct me if i'm wrong but you are moving a mailbox from 2007 to 2013, is this correct? Also, what version is the source and target such as SP and CU? Does this happen to only 1 mailbox or some or all? 

Hi,

Install latest update to Exchange 2013 (CU9) and then try it again.

Hi,

How about the issue? Any update?     

Regards,

David