I am using Veeam ONE client and if I launch the console on a monitored hypervisor I get: Invalid or expired session ticket. It will NOT accept good known credentials for the hypervisor in question.
I am using 9.5.4.4566 and it is fully licensed and other than this issue I can see my monitored servers, all functions appear to work just fine from the GUI, etc except this console issue.
It seems like the issue relates to the version of VMRC. Our built-in version is 10 and you're using 11. Can you try installing a lower version of the console on another computer and check if you have the same issue or not?