I ran Webroot SecureAnyware and it says nsbu.exe has a possible handle leak. Webroot SecureAnyware is much like McAfee scan plus. The only thing it does is scan the computer. It does not try to protect it. So the odds of conflict with Norton is low.
I am running Norton Security with Backup plus v. 22.5.5.15
Webroot did provide a "full log" but it did not look like it gave any information, other then standard system info and a list of what it had scanned. That is likely because I got it from Geek squad and the idea is, you scan the computer, it throws errors, you pay them to fix it. :l This problem however, only Norton can... legally fix.