Hi...
First U have to install client 5.1 to connect to ur esxi enviroment.. as the highest version is 5.1...
Second, for vmware guest console, check this link:
http://www.gkhan.in/mks-internal-error-on-vmware-console/
For Client 5.1 VMRC Error:
http://communities.vmware.com/thread/333026?start=30&tstart=0
Read last page posts, talking about killing certain process then uninstall client then reinstall
FIXED: The VMRC Console Has Disconnected - Windows 8
Which client to install for windows 8
Hope it helps 