First of all, I've read all the relevant questions here I could find... I use RealVNC to connect to my computer at home - everything worked without any problems, but today I couldn't connect from work. Over the weekend I was OC-ing my computer and now I noticed that the internal IP was changed to 192.168.0.6 (from 192.168.0.2) which is a bit weird as I have reserved the 0.2 address to my MAC. But anyways, I've to change the port forward to 0.6 but that didn't work. After router reset, I got the 0.2 address back so I've changed the port forward back to 192.168.0.2, but I'm still getting connection refused error. Windows firewall is set correctly, the VNC server is running as I can connect via the internal address but connecting using the external IP gives me an error.
Edit: OK, I see I cannot connect from local network using external IP, but when I use RealVNC iphone app and 3G connection only I can connect which is all I need ...