Dear Koster, thank you very much for your response...
yes, I had to type out strings of wierdly shaped characters and quite frankly I found it a bit of a pain in the neck 'cos it took about ten minutes....each time I typed out the set of characters I was then presented with a further set/s but eventually the sequence ended and I was able to get on with my emails proper.
If you have to repeat it, that's because you didn't copy it correctly the first time. You need to copy it exactly, meaning that capital letters have to be capital letters and lower-case ones have to be lower-case ones.