When I upgraded it asked me to create a Microsoft account but I assumed that this would be a new account and one that I would not need to use so I did not need one and put junk information in.  I then found out that this information had been used to change MY OLD LOCAL ACCOUNT to some online Microsoft one.  I now cannot log into that account as I do not know the password I entered or the junk telephone number i entered.  I do not want an online account but mostly I want to be able to access my old files on this computer.  As it is no longer a local account I cannot change its password on my PC.  There need to be a lot of warnings that your local account is going to become an online one.

I assume if I create a new local account with the same name as the old local account this will not miraculously give me access to my old files?

This is a shambles and by far the worst Windows upgrade I have done.

Why should I be forced to have a Microsoft account when I did not before hand?