Cannot move Exchange 2013 "Discovery Search Mailbox" to DAG database! :(

Question

I  want to get rid of the default mailbox database but it won't allow me because it says it still have mailboxes. I ran:
"Get-mailbox -database "Default Mailboxdatabase name" and it shows the "DiscoverySearchMailbox" still there. I was able to move all the other arbitration mailboxes to my DAG database.
I then ran:
Get-mailbox -database "DB Name" | new-moverequest -targetdatabase "DB Name"
and
Get-Mailbox -Filter { RecipientTypeDetails -eq "DiscoveryMailbox" } | new-moverequest -targetdatabase "DB Name"
and both times I receive a long error:
MapiExceptionMdbOffline: Unable to make connection to the server. (hr=0x80004005, ec=1142)
Diagnostic context:
    Lid: 41192   dwParam: 0x1
    Lid: 49384
    Lid: 51176   StoreEc: 0x476
    Lid: 48104
    Lid: 39912   StoreEc: 0x476
    Lid: 41192   dwParam: 0x2
    Lid: 49384
    Lid: 51176   StoreEc: 0x476
    Lid: 48104
    Lid: 39912   StoreEc: 0x476
    Lid: 41192   dwParam: 0x0
    Lid: 49064   dwParam: 0x1
    Lid: 38439   EMSMDBPOOL.EcPoolConnect called [length=48]
    Lid: 54823   EMSMDBPOOL.EcPoolConnect returned [ec=0x476][length=20][latency=0]
    Lid: 53361   StoreEc: 0x476
    Lid: 51859
    Lid: 33649   StoreEc: 0x476
    Lid: 43315
    Lid: 58225   StoreEc: 0x476
    Lid: 39912   StoreEc: 0x476
    Lid: 54129   StoreEc: 0x476
    Lid: 50519
    Lid: 59735   StoreEc: 0x476
    Lid: 59199
    Lid: 27356   StoreEc: 0x476
    Lid: 65279
    Lid: 52465   StoreEc: 0x476
    Lid: 60065
    Lid: 33777   StoreEc: 0x476
    Lid: 59805
    Lid: 52487   StoreEc: 0x476
    Lid: 19778
    Lid: 27970   StoreEc: 0x476
    Lid: 17730
    Lid: 25922   StoreEc: 0x476
    + CategoryInfo          : NotSpecified: (:) [New-MoveRequest], RemoteTransientException
    + FullyQualifiedErrorId : [Server=LA3-EXMBW002,RequestId=cb04b084-0dd7-46b9-bf57-6d3317013d47,TimeStamp=3/14/2014 10:44:34 PM] 7A53F855,Microsoft.Exchange.Management.RecipientTasks.NewMoveRequest
Any ideas on moving that Discovery Mailbox? Thx!

Answer 1

MapiExceptionMdbOffline: Unable to make connection to the server. (hr=0x80004005, ec=1142)
That error indicates that the database is not mounted, so mounted and try again.
 A workaround if you can't move the mailbox, is to rehome the mailbox to another database.
 Example:
 Get-Mailbox Discover* | Set-Mailbox -database <DB Name>
Martina Miskovic