Yesterday I upgraded from 12.0.636 to 12.0.672 and now I cannot start Houdini any more. I get a “License Error: Unable to connect to hserver for license acquisition” message but sesinetd is running and license administrator is connecting and tells me everything working ..
I contacted support but got no reaction till now..
Anyone experiencing the same ?
Slowly I am getting a little bit nervous because of my deadline on friday ..

I also tried reinstalling and also tried downgrading to 12.0.671 but till now nothing helped ..

Downgraded to 12.0.634
disabled all other network cards in the computer.
disabled AV and Firewall
Restarted sesinetd n-times
restarted the whole machine n-times ..
Still the same. License Admin tells me everything is OK.
All other apps bail with
License Error: Unable to connect to hserver for license acquisition
Houdini, hython, etc all fail with error message.

:cry:

mail to support@sidefx.com with diagnosic information from the license administrator
sometimes license gets corrupted and they provide you a new license file ))
I almost had the same problem.
good luck

I did mail them the diagnostic info file today in the morning, but I didnt get any response till now, so I thought maybe I can solve the problem in the forum ..
thanks for your response.

Problem solved by uninstalling all versions of houdini and hqueue server and client. Then reinstall H12. The problem was that hserver service was not installed by the installer. No idea why, but simple reinstall was not enough.
But wanted to share in case someone hits the same problem.

Damn it. The Problem reappeared after installing 12.1.41. I did install it without the license server but the installer did mark the service hserver for deletion. then I reinstalled houdini with license server. Now the license tool works, the sesinet service is running but I still get this error : License Error: Unable to connect to hserver for license acquisition

Now I am quite desperate, because this time there is now visible problem to adress ..

The problem was that windows didnt install the service hserver.exe ( even after complete uninstall / reinstall ..)
If you dont want to trust the installer anymore there is a way to manually install the service, which worked like a charm for me.

sc create HoudiniServer binpath= c:\windows\system32\hserver.exe

and be carefull about the space after binpath= !!! this cost me half an hour to figure out this damn space …

Support told me that there could be issues with the hqueue service on windows. Next time I if the problem occurs I will stop the hqueue services before reinstalling houdini ..

stopping hqueue service before re-installation did the job for me.

Just had the problem again with houdini 15.5.632 and windows 10 x64.
Again the sc create HoudiniServer binpath= c:\windows\system32\hserver.exe saved me ..
Its really cursed. Whenever time is short houdini licensing stops working …

Had the same thing but found that Houdini Server service was turned off, now works after starting that.

This happens the same day as H16 was released and I also just installed Unity. Can't be sure but my money is on Unity to be the guilty part as that install took issues with other network apps.

Had the problem too with the upgrade to Houdini 16. I guess it comes from the mixture of licensed houdini and apprentice. I owned houdini up to 15.5 but now I am just testing houdini 16 in apprentice mode parallel to my commercial old licenses. My suspicion would be that the installer of houdini 16 apprentice uninstalled the license server.
I had to reboot once and the sc create HoudiniServer binpath= c:\windows\system32\hserver.exe
worked . Before reboot windows would claim that the hserver is marked for deletion. and sc create would not work.

Sounds like it was the H16 upgrade then. IT might have updated the license server without telling anyone.