You'd have to provide more details. Your IP has nothing to do with whether or not you can connect. However, a different ISP (your internet provider) *might* cause the problem. Some ISPs don't allow IRC... at least, not on standard ports. It's also possible that your ISP isn't allowing DNS resolution for certain addresses (Verizon does this for many IRC addresses). If you provide the exact error message(s) from your status window, that will help to determine the problem. You might also want to try connecting to the server's IP address instead of the DNS address (123.123.123.123 instead of irc.somenetwork.net). [those are examples and not valid]
