This is not the same.
VC talks to ESX HOSTS on ports 902,903 (as the VI client) and 27000,27010 (License server),
furthermore ESX HOSTS talk each other on ports 2050-5000, 8000, 8042-45
Are them all opened?
try making a telnet from VC to ESX HOST on port 27000 or doing a netstat -n on VC to see the opened and time wait connections
Matey, I had this same error....Drove me CRAZY... we run ESX 3.0.2 and Virtual Infrastructure/Center 2.0.2
I also noticed, under the permissions tab in Virtual Infrastructure when logged into the server directly (eg not via VC), that instead of the usual "servername.domain.com" in the "defined in" tab, that they had "this resource" listed instead of its own "servername.domain.com".
To be able to ADD ESX HOSTS and get rid of the "A General Error has occurred: Internal system error", you need to type these commands in the console...
a) cd /etc/vmware/hostd/
b) ls (you should see authorization.xml config.xml, env, environments.xml esxinfo.vha and hostsvc.xml
c) type "mv authorization.xml authorization.xml.old"
This will reset the authentication stamp on the file that is responsible for adding the ESX host to Virtual Center***
d) restart the vmware management service by typing "service mgmt-vmware restart"
Then ensure the ESX host you are trying to connect is REMOVED, THEN READD it.
This should work! It did for me thanks to the guys at Tech Support....! they are guru's...I would never had found this