We currently use UltraVNC on about 2000 computers (mostly 1.1.9.6). We randomly get server that stop responding. We restart the service or reboot the machine and everything start to work again.
Recently we installed 6 Windows 7 "Tools" who crunch data whit a CPU intensive program. On that group of tools specifically, the random server problem is getting a real problem. I need to restart services on that group 2-5 times a week each.
The symptoms are always the same: The viewer is getting to negotiating protocol and stop there. No password box or anything.
On the server side, we can see 2 winvnc.exe process running. Our "patch" is to kill those process and restart the service.
I specify the hight cpu usage, but i what to say that on the time the connection is attempt, if the cpu is at 100% usage or completely idle the problem is exactly the same.
Is this a known Issue?
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Vnc Server stop responding
Re: Vnc Server stop responding
I'm running into the same situation.
VNC server is running on a Windows 8.1 x64 machine as a service.
Regards
Arno
VNC server is running on a Windows 8.1 x64 machine as a service.
Regards
Arno
Re: Vnc Server stop responding
Yes, We used to see this issue a lot on older (1.0.6.5, 1.0.8.2, 1.0.9.x) versions.. It still happens for us on 1.1.9.6, but much less frequently.. Guessing that it is a race condition of some type? On the older versions, it seemed to happen frequently when we closed a maximized 16 bit application..
- Rudi De Vos
- Admin & Developer

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Re: Vnc Server stop responding
I could repeat it with the older versions, but with the 1.0.9.6 viewer i always connect.
For testing i use the "network emultaion toolkit"
http://blog.mrpol.nl/2010/01/14/network ... r-toolkit/
The little tool that can simulate very slow networks.
If you are able to repeat it with some settings, please let me know.
For testing i use the "network emultaion toolkit"
http://blog.mrpol.nl/2010/01/14/network ... r-toolkit/
The little tool that can simulate very slow networks.
If you are able to repeat it with some settings, please let me know.
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