The server has no password set. To set it the first login will vnc will require you to set a password.
Log into https://my.interserver.net
On the main page select your VPS package. For example https://i.is.cc/qsG5vzV.png you would clikc under name the windows vps id.
On the next page on the left side click VNC (http://i.is.cc/qsIRat0.png)
Then click connect to desktop with HTML5 vnc (http://i.is.cc/qsLNUbi.png)
If your browser does not support java or html 5, instead on this page click the link that says click HERE to grant your IP access to VNC (http://i.is.cc/qsQ7yqS.png)
Your IP will be auto detected with in IP To Allow VNC Access To. If you run a proxy you may need to change this IP. Look above for VNC IP:Port which has the IP and port you can vnc to, after you click Update VNC.
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