The semaphore timeout period has expired - SSR 2013

Server1 has SSR 2013 installed.  Server2 has SSR 2013 agent installed.

Server1 has external USB3 drive shared over the network.  Server2 backups to this share over the network.

I am getting the following error message when doing backup using  Symantec System Recovery 2013 from a server to a local share.

--Unable to write to file.

--Error EBAB03F1: Following Operating System error occurred while performing requested operation: 'The semaphore timeout period has expired.'

--Unable to set file size.

--Error EBAB03F1: Following Operating System error occurred while performing requested operation: 'The specified network name is no longer available.'

(UMI:V-281-2001-31)

Any ideas?