Sharky
I didn't for one moment think the pop-up had anything to do with this site directly. Tonight, all I've done is log on, I'm on Tesco.net, and came straight to these boards. I was much relieved as I couldn't get on earlier and felt as though my blood supply had been cut off!!!!!
I will check my apps (I think, not being very computer literate) but cannot think of anything I've been into that I haven't been into before.
Will let you know if it happens anywhere else (only 2 so far) It is not pictures or anything just an 'invitation!.
Thanks for your help.