Thanks for that! Perhaps it's not as serious as I feared.
I installed & ran that free checker. It said it found 880 problems. Then it offered to fix them if I bought the programme (otherwise it would fix just 15 of them!)
I let it fix 15, then decided to run my own checker, System Mechanic 6, which generally finds a lot of errors & fixes them.
It found & cleaned 289 junk files & 40 'privacy violations'. Next it found & fixed 2 'invalid dynamic link libraries' and 2 licensed software keys with problems. Finally it found something it normally doesn't: 'Invalid folder & filename references' (155). It fixed 152 & said it couldn't fix the other 3.
So there you have it. I'm still not sure whether to delete the file that was originally highlighted.
Finally I've started the AVG scan again to see if the trojan is still being flagged.
Thanks Mat. (Sorry I've been away from the computer for a while.)
I ran the test. It took 45 mins & found 142 'hidden objects' relating to programs, zone alarm & service packs, etc. (It's not possible to copy/paste the list.) No breakdown or further identification was provided in the results.
The question remains should I delete the suspect file or leave it & assume it's a false positive?!
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