This solution is not exactly for this problem. When I saw
<html><b>Error : Failed to add License Code "UNKNOWN" to the license server on host "no-net".</b></html> I felt this could be a workaround
Yes this sort of a issue I faced around a year back. I had to update my host file which solved my problem. I did that as I was asked to do at that point of time and not explored much on it. Thought this could solve the problem for this case too as it had something to do with License server
I do respect your expertise on the field I just tried to give another perspective to solve the issue. If it doesnt work Doyana always got an alternative to go by FordsRock suggestion
It is because you are trying to install a Seat License while being connected using Remote Desktop (Terminal Client). You need to be behind the actual screen (or console), otherwise it only will let you install a concurrent license.
(Actually when you start QTP it explains exactly this, but I didn't notice the first, like, 300 times I tried).