Sorry, but in trying synchronise the ID I use on my laptop with the one I use on my desktop, I've done something wrong - probably several things - and in effect cannot now change/correct the credentials on either machine. Also, if I log out at all, I don't think I will be able to get back in. Oops!
One thing which seemed to go wrong was my "secret question" - the definitely correct answer was not recognised.
Help!!!
David