having difficulties in remote assistance to agents ( Computer)

having difficulties in remote assistance to agents ( Computer)

Dear Team

I'm new to Desktop Central, I have no issues with deploying patches for the agents.

I'm trying to use remote assistance to agent ( Computer ) via Remote control, a windows pop out , failed to load. with the Error message "websocket connection failure. error normal closure" .

ports open ; 8383, 8443  ( at Agent (computer windows defender firewall) , and at server ( window defender firewall). firewall is opened for the ports above .

Anyone encounter this error before?

Thank you
Kelvin