I just ran a full Norton scan, which found no spyware, viruses, or other risks. Yet I keep getting a popup from the “exclamation point in a yellow triangle” icon from the lower right corner of my screen which says my computer is infected with the latest version of the aforementioned PSW.x-vir trojan.
You’re not actually infected with anything. Those popups are generated by so-called “rogue software”; while not actually a virus or dangerous malware, they are underhanded attempts to get you to buy software to eliminate the fake “virus” threat it keeps warning you about. The best software I’ve found for dealing with these is SmitFraudFix.
As I suspected, but being something of a computer-owning neophyte (I just bought my first home computer after being a programmer for 20 years!), I wasn’t sure.