Hi Brian,
Thanks for the update. Please allow me to explain something about the suggestion to run Malware Bytes. There is NO single anti-virus, anti-malware utility which is the end all and be all of virus and malware detection. There is no single software program which does it all or catches it all.
Successfully fighting virus's and other malware is a comprehensive program which includes the right tools (various software) and even more importantly proper vigilance and safe internet practices of us, the end user. One wrong click and and you could give a malicious program the chance to install itself on to your system.
But most importantly there are new virus's and other malware being written all the time. Companies like Symantec, McAfee and so many others are in a constant batlle against the bad guys. Unfortunately the reality of malware is that they are ahead of the curve, in some ways they have the advantage because they are constantly inventing new ways to circumvent the protection offered by your anti-virus software.
The reality is that this puts Symantec and other companies in a position where they have to be reactive to new malware. Symantec has a consistent track record of reacting very quickly to new threats and constantly scores very high in terms of the over all protection offered to you, the end user.
Combine this with the fact that there are many methods of detecting various kinds of malware, some methods are better at catching certain things than others.
You would be doing yourself a disservice to think that this applies only to Symantec. Not one single company has ever written software which catches everything.
You will find this to be a consistent statement of all veteran contiributors throughout the NIS and N360 forums, not to mention any other anti-virus support forum you might visit online. Perform your own searches here on the NIS and N360 forums and you will find this to be the case.
Another thing I wanted to mention. It is never advised to run more than one real-time anti-virus software on your computer because they will in all liklihood interfere with each other and actually create more problems than they solve. The free version of Malware Bytes (which I recommended you run) is a passive scanner only so it co-exists peacefully with N360.
That said, my goal is to help make sure you don't have any problem on your computer, so yes I recommend running Malware Bytes. Malware Bytes does indeed catch things sometimes which might not have been detected at that time using N360 or NIS but the same could be said in reverse even more often.
Hope this helps explain why you see this recommendation frequently on the Symantec forums.
Thanks
Allen