I appreciate being saved from pain, but I don't yet know the name of anything anything more efficient than CA.

Thanks for the tip about scanning downloaded files before opening - I've done this, admittedly using CA Virus Scan, and nothing detected.

However - I have downloaded some so called mp3s which appear ok, but when I click to open, they open Media Player with a message about extension does not match file format, then when I click the play button, it opens up two IE7 windows - a ****** [ < edit - these asterisks appeared where I typed the word C-A-S-I-N-O] .... and a Dating site - pretty dodgy - so if you know how to avoid that stuff, I'd be grateful.
What do you use to scan safely?

Cheers.