Migration from Exchange 2007 to 2013 gives error "Failed to communicate with the mailbox database'

I have been trying to migrate several databases from Exchange 2007 to Exchange 2013. The migration started successfully, and many of the mailboxes moved successfully (about 70). The remaining mailboxes, failed. Looking deeper, we found a few issues; The two 2013 Mailbox servers were on different versions. The Server had run out of disk space, and the NIC drivers needed to be updated.

Now when we try to migrate a mailbox that had failed in the earlier batch, we get the following error:

Data migrated:                        
Migration rate:                        
Error:                        MigrationTransientException: Failed to communicate with the mailbox database. --> Failed to communicate with the mailbox database. --> MapiExceptionNetworkError: Unable to make connection to the server. ‎(hr=0x80040115, ec=-2147221227)‎ Diagnostic context:    ......    Lid: 9624    dwParam: 0x0 Msg: EEInfo: Detection location: 501    Lid: 13720   dwParam: 0x0 Msg: EEInfo: Flags: 0    Lid: 11672   dwParam: 0x0 Msg: EEInfo: NumberOfParameters: 4    Lid: 8856    dwParam: 0x0 Msg: EEInfo: prm[0]: Unicode  string: ncacn_ip_tcp    Lid: 8856    dwParam: 0x0 Msg: EEInfo: prm[1]: Unicode  string: <Server FQDN>    Lid: 12952   dwParam: 0x0 Msg: EEInfo: prm[2]: Long val: 3749909585    Lid: 12952   dwParam: 0x0 Msg: EEInfo: prm[3]: Long val: 382312662    Lid: 45169   StoreEc: 0x824         Lid: 50544   ClientVersion: 15.0.847.32    Lid: 52080   StoreEc: 0x824         Lid: 44273      Lid: 49064   dwParam: 0x1    Lid: 37288   StoreEc: 0x6AB         Lid: 49064   dwParam: 0x2    Lid: 59431   EMSMDB.EcDoConnectEx called [length=203]    Lid: 51239   EMSMDB.EcDoConnectEx exception [rpc_status=0x6D9][latency=0]    Lid: 62184      Lid: 16280   dwParam: 0x0 Msg: EEInfo: ComputerName: n/a    Lid: 8600    dwParam: 0x0 Msg: EEInfo: ProcessID: 3460    Lid: 12696   dwParam: 0x0 Msg: EEInfo: Generation Time: 0414-04-07T16:32:03.2100000Z    Lid: 10648   dwParam: 0x0 Msg: EEInfo: Generating component: 2    Lid: 14744   dwParam: 0x0 Msg: EEInfo: Status: 1753    Lid: 9624    dwParam: 0x0 Msg: EEInfo: Detection location: 501    Lid: 13720   dwParam: 0x0 Msg: EEInfo: Flags: 0    Lid: 11672   dwParam: 0x0 Msg: EEInfo: NumberOfParameters: 4    Lid: 8856    dwParam: 0x0 Msg: EEInfo: prm[0]: Unicode  string: ncacn_ip_tcp    Lid: 8856    dwParam: 0x0 Msg: EEInfo: prm[1]: Unicode  string: <Server FQDN>    Lid: 12952   dwParam: 0x0 Msg: EEInfo: prm[2]: Long val: 2767313664    Lid: 12952   dwParam: 0x0 Msg: EEInfo: prm[3]: Long val: 382312662    Lid: 59505   StoreEc: 0x824         Lid: 50544   ClientVersion: 15.0.847.32    Lid: 52080   StoreEc: 0x824         Lid: 36081      Lid: 51152      Lid: 52465   StoreEc: 0x80040115    Lid: 60065      Lid: 33777   StoreEc: 0x80040115    Lid: 59805      Lid: 52487   StoreEc: 0x80040115    Lid: 19778      Lid: 27970   StoreEc: 0x80040115    Lid: 17730      Lid: 25922   StoreEc: 0x80040115

All of the issues listed above have been corrected, and all of the databases are mounted. Users are able to send and receive mail, but I can not migrate mail using the Migration Batch utility.

The destination server is a Hyper-V Guest running Server 2012, SP1, and Exchange 2013

The Source Server is Running Exchange 2007.

I have tried doing a test move to another destination server that is also Server 2012, and Exchange 2013, and the migration also failed.

I would appreciate any help you can give me!

Thanks,

Jon