I have C5-03 and every time I try to connect to WLAN, I get same message: “Invalid server name.” How can I can fix it?
It sounds like the settings for your internet profile are messed up. Try contacting Nokia so they can provide you the correct settings.
Have you updated your phone software?If not you can do it by installing Nokia Ovi suite on your PC.
After installing Ovi suite connect your phone to PC via USB cable and the suite will ask you to create an Ovi account or login with your registered account.It will automatically check for software updates.Install the updates(126MB in size).
If updating doesn't works for you then ask for help in Nokia priority dealers in your nearest locality.