Check duplex on both hosts aswell as ports in the network switch where both hosts are connected. Sounds like a network issue.
Beside checking the network stuff: Does this VM have any ISO mounted which is not available from the target host? I often see cold migrations fail cause of this "problem".
I agree. We had the same problem. The issue went away once we made sure that the service console connection was at 100 full duplex on both ends.
machine_a was at half duplex and machine_b was at full (Service Console). To make a log story short just ensure that your service consoles are setup the same.