Sometimes when you are in the console in vc you get can't connect to the host error.  Ususally to get around that I restart the virtual center service on the server that has it running.  If that doesn't work I ssh into the esx server and issue the following command with root.

service mgmt-vmware restart

Then close out of all your virtual center client windows and login again to vc.  The console for the vm should pop up.