Another VNC problem need help

[marvontherim]

I have had VNC installed 2 years ago on all 4 computers in my home.
It was working great for 6 mo than stopped. Not sure what caused it. Since than I have installed Tight VNC and today Ultra VNC. I can access one computer but not the others.
I can't seem to understand how to get each computer to view the other.
Do I have to install ultervnc on each computer?
Is there spy software blocking access?
Should I uninstall and start over?
Not sure how to set up accurately.

Any help would be appreciated.

Thanks

[oracle128]

The VNC server (called vnc.exe in UltraVNC) needs to be installed and running on each machine you want to control. The VNC Viewer needs to be installed and run only on those machines you wish to use to control the others.
Firewalls will block VNC access. To allow it, you can either allow the VNC server in the firewall config, or open the required port. The default port for UltraVNC is 5900. It's possible that anti-spyware/anti-virus will detect VNC as dangerous. Windows Defender does. These programs will tell you, and ask you what you want to do. If they don't, they won't be blocking it.

If you want to VNC remotely via internet, you will need to set up port forwarding on your router. If you allow VNC access to multiple computers, each one will need to be on a different port, so you can forward the right ports to the right PCs.

[marvontherim]

I'll try that.