It worked:dance: (Think I might have got the right icon this time!)
After it had done KB4034664 and restarted, I let it do the other 20 odd "important" ones and they went thought OK too.
Donation already sent.
Brian you are a star! I started using computers when the UI was hand switches and 5-track tape, wrote compilers for what we then called super-computers and taught computer science for 30 years, but the vagaries of Windows Update are beyond me. Well done sir!
One question, you said at the beginning of this that problems can occur if IE11 is not kept up to date. I don't use IE11 but I have noticed that optional updates for it are sometimes offered. I ignore these, but from what you say this is not the right thing to do?
Malcolm