Thanks Dave - but I was referring to pop-ups that were appearing on this forum in messages on this thread.
I've noticed two so far, one on Rod Stradling's message about the Musical Traditions Albums, and another on a message from Dick Miles - a blue-highlighted word opens up a pop-up.
Both normalised as shortly after they appeared, so I assume they have been dealt with elsewhere.
My personal problems have been identified as currently circulating viruses (I suppose that should be Virii) and are being dealt with.
When my PC is sorted (later today, I hope), I'll drop in my lap-to, which seems also to be under attack.
Thanks for the advice.
Jim Carroll