OK, I am ashamed to be asking this, for two reasons, but can anyone tell me how to solve it, please.
I am ashamed first because I have to confess to reading the Daily Wail, and also because I should be able to solve this.
What happens is that when I go onto a couple of websites, the DM is the one it seems to happen on mostly, the computer freezes and then this message pops up. It happened earlier while I was booking a ticket on the Stena Lines website.
It doesn't happen on my newer Lenovo with W8, it's on my older Asus with W7 Home Premium SP1, and FF26.0. The machine has 2GB RAM and a (TM)2 CPU T7200 @ 2.00 GHz 32 bit. No idea what that means, I just copied it.