Windows Blank screen Issue

[bhongya]

Hi.

I am facing blank screen issue when I connect to Windows 2012 or Windows 2016 server. I am running vnc in service mode.
In user mode, as long as Windows RDP session is active then only I can use VNC. The moment I close or minimize RDP session the VNC session does not respond to any input.
If I try to connect in service mode, I see only a blank black screen and does not respond to any user input. Is this a known issue?
I have tried installing ultravnc 32-bit and 64-bit both one after another.
I have attached snapshot of the vnc server settings. Please help resolve.

[Rudi De Vos]

In user mode, as long as Windows RDP session is active then only I can use VNC. The moment I close or minimize RDP session the VNC session does not respond to any input.

This is how it works in user mode. vnc clone the RDP buffer, but RDP disable his video buffer on minimize or disconnect.

It should work as service.
In that case you clone the real video card and console monitor.
[v]RDMmode
You can also play with this option.

poll option
[v] desktop duplication... need to be supported by the videocard ( some virtual machines lack a correct driver)
Disable it for testing

It could also that your system doesn't detect any monitor to clone, if no console exist vnc can't clone it.
Most video cards support an overwrite to tell a monitor is connected, even when not plugged.

[bhongya]

Thanks for the reply.
I am facing this issue on Google cloud VPS. I am not sure whether this is the root cause for the problem as its a cloud VM. Any inputs on that front?

[bhongya]

Its the same problem that other people are facing on Google cloud platform . One of the references - https://www.reddit.com/r/sysadmin/comme ... p_windows/

Someone from ultravnc team should try to reproduce. Thanks