Host has an agent that is not in a responding state.

Hi All,

As seen in the title I get an error when trying to live migrate a virtual machine. All worked find until upgrade to system center 2012 VMM - Full error is;

Host Server.Domain.local has an agent that is not in a responding state and is not available for placement.

Select a different host and then try the operation again.

ID: 23790

Can do everything else on the hosts just can't migrate. 

Help much appreciated!

James