Only able to fix runtime error by uninstalling Norton Internet Security?

After reading online comparison testing, I decided to replace my ESET security/antivirus software by purchasing the latest version of Norton Internet Security. I ran the update feature to make sure everything was current. But I immediately started getting the following error message in Firefox about once every 20 seconds (followed by Firefox freezing for a while)...

   Runtime Error
   Program: C:\Program Files\Mozilla Firefox\plugin-container.exe
   R6030
   - CRT not initialized

 

I'm aware there was an issue with the Norton toolbar. However, not only did I have the most recent versions of both Norton IS and FF, but I also tried disabling the toolbar in Firefox. No luck. I tried running Firefox in the "safe mode." Same error. I tried a complete uninstall and reinstall of Firefox. Same error.  So, I tried uninstalling Norton. The error went away and Firefox works fine. When I posted in the Firefox community forum, the advice was to get rid of Norton. Is there no other solution? My setup below.

 

WinXP Pro SP3 4GB RAM, 500GB C drive 20% open/unused, regular defrag/backup/error checks/etc.