Thank you BRYNIT for your 'CLICK HERE' list. Unfortunately no clear answer emerges. One thinks I need a better copy of the file, and tells me how to get it. Another seems to see it as malware, and tells me how to get rid of it. Another says it's probably a Registry error (CCleaner found no fault there, though). And so on ... And, of course, the usual "Let us repair the 2815 errors we've discovered on your computer" ads. It hasn't appeared so often lately, so for now I'll keep an eye on it but otherwise leave well alone. And thank you for taking the trouble - yours was the only reply. (At least it can't be a widespread and major problem.)
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