Even after removing Norton and everything with it, I still am getting a message from Avast saying that Norton is installed, so the scanner can’t be enabled. Norton still also shows up in the Windows Security Center. The operating system I’m using is Windows XP SP2. I’m using the very latest version Avast. Thanks for any help you can throw out.
Hi and welcome ,
if you were to use search for “uninstall norton” you would find links for uninstallers included in about every third or fourth topic.
follow that up with a decent registry cleaner and then you should have no problems installing Avast . you might have to remove Avast to clean norton out properly first though.
good luck 
This is a program removal tool, which can remove (the remnants of) a number of different Norton Programs:
Removing your Norton program using SymNRT
Got it fixed last night, thanks. After doing all those files the Norton website told me to run, I found out that they don’t work on Norton SystemWorks 2003 Professional, which I neglected to tell you. There was a link, however that showed you how to remove Norton SystemWorks 2003. Out of that, there was only one key in the registry that I did not delete and one folder in the computer that I did not delete. Those two things apparently were all it took for it not to cooperate. The Windows Security Center still showed Norton was installed and up-to-date, but I decided I’d install Avast anyway and see what I got. I restarted the computer with no messages about an incompatible AV. Restarted the computer again to make sure - still no message. Also checked the Security Center again and now it says that there is one or more antivirus software on the computer and it is reporting that at least one is up-to-date. So, it’s now going. Thanks.
Why?
I think you’ll have trouble sooner or later… the two drivers (antivirus) will crash and conflict…
Better a full removal of NAV. You can keep all other Systemworks applications, except NAV.