VIX API - There was an error in communication

Hi,

I cannot execute any VIX API vmrun command once the Virtual Machine is powered on.

I can list all virtual machines, and power the machines on, but once the machine is powered on, every vmrun command fails with the error "There was an error in communication"

The VIX API is installed on a different computer of the Vmware Server (Host) .

Both firewalls are turned off.

Does anybody know what can be the problem?

Thanks.