my other computer requests proxy authentication . i can not launch norton or get to the internet
Assuming this is a Norton issue and not a general connectivity question, you should find Network Proxy Setting configuration options in Norton's Miscellaneous Settings.
i can not launch norton to chech these settings
Welcome to the Norton Community Forum
If your computers require proxy settings, please go to your control panel and Internet Options, Connections and configure your network settings from there. That may get you onto the net. However, if you can not open up Norton's, is your subscription still current? What Norton product are you referring to and what version is it please? What operating system and service pack and is it 32 or 64 bit please?
Another possibility is that malware is causing your problems.