I run Windows ME and had old version of Norton on. I uninstalled it and got the new one and i cant get it to work keeps saying "The setup has detected that a previous install or uninstall has completed but requires a restart" I have done this a few times and the messages still keeps coming on.
The main reason for this happening is the failed unistallation of the previous version, if you can re-install the previous version then un-install it, then put in NIS2004.
If you can't re-install it make sure that it has not left it's self in the registry keys, if so delete them and all common/shared files and then you should have Joy.
I had exactly the same problem and it took about two days to solve using the symantec online web assistance it is very much trail and error and learn as you go but stick with it and you should come good.