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I might be being premature but it's looking good! I did a system restore and it worked (when I've had to do them in the past they sometimes don't work ... usually a bad sign, means your system's been pretty badly screwed up for a while I guess).
Anyway, Buenchico, your timely advice might just have saved me some serious headache. When something goes wrong with the computer I really feel it, as though it's personal, not just the damn computer. And what I wouldn't do to those ... 'people' that write those viruses ... don't get me started!
If it all goes pear-shaped again I'll let you know, maybe you can give me another headache tablet!