I would encourage you to check network ports according TechZone link below:
Network Ports in VMware Horizon 7 | VMware
It seems to be a network port issue.
Thanks for the reply
We have checked both 443 and 8443 ports are enabled from our end
As you're tunnelling connection through UAG, check if you disable all gateway services on Connection Server
An check from UAG side if Edge service configuration is properly set
If you have a load balancer in front of the UAG's make sure the session is set to be sticky/persistent i.e. once the user Authenticates (Primary Protocol) the (Secondary Protocols) goes down the same path.
A quick way to test is power down the other UAG's and see if the problems still exists. The UAG's can handle 2000 sessions so as long as you are not near this you should be fine for a test.
did you ever get this resolved? we're having the same issue - all ports seem correct
We are also having the same Issue only from the public internet!
I have opened a case with Citrix and nothing from their side and now with Vmware still investigating.
did you receive an answer from either citrix or vmware?