Proxmox VNC client access

 If you are running proxmox and you would like to connect to one of your Virtual Machines via a local VNC client, then you have to change the setup at the general proxmox instance.

1. Go to your proxomx web interface

2. select your main proxmox node and go to your shell

3. change to folder /etc/pve/local/qemu-server

4. use "nano" to chnge content of your config file of your VM. Th enam eo fthe config fiel relates to the instance numbering you have defined, e.g. 101, 102 ...

means use: nano 101.conf

5. add the follwoing line at the end of the document:
args: -vnc 0.0.0.0:77

where 77 is the "key" by which you will be able to connect to the VNC server of your VM.

6. Now save.

7. MOST IMPORTANT hint which is not described at the official proxmox documentation: 
restart your VirtualMaschine to which you would like to connect. For me it takes several days to to figure out why connection iwas not working until i finally rebootet the virtuial maschine by accident...

8. No you can user your local VNC client to connect to your vm.
You can do this by connect to the IP address of you proxmox server and use the port 5900 and add value of the "key" we specified before. in the example mentioned above it s 77. means the portnumber would be 5900+77 = 5977

reference: VNC Client Access - Proxmox VE