How can I set up my Nokia N800/N810 to connect to the internet via a proxy server?
You can change this setting by navigating to Tools > Settings > Connection > Advanced Connection Settings
If you’re having problems with Skype calls, check that your internet connection is working properly. The easiest way to test your connection is by attempting to browse the internet.
If the internet connection is working properly but you are still having trouble making Skype calls, please visit Troubleshooting section of the Skype Support website.