Hello Quinton - Alex and Tim have provide valid suggestions to this issue. Usually this will occur when the hostname / machine name / IP Address is not recognized by the proxy service. Since you are allowed to log in, you DO have assigned the appropriate access pass.
Take a look at the proxy setting and see if Tim's suggestion addresses the issue. If so, please mark the appropriate replies as helpful / correct so our team and other members know that your question(s) has been answered to your satisfaction.
I have the same problem. I did added the ip of the server i have installed Qlik Sense. But i am still facing the Issue.
surprising thing is i can access the the hub on the server but not on other nodes. but i managed to view the qmc on that other node. so my question is, am I missing some configurations. Also just to be sure do i need to allow the port 4244 and port 4248 on the network firewall?