I had an expensive computer tech help me with a problem.  Turns out he didn't know much more than I did.  I am running five computers tied together with Windows 10 Pro networking.  After he left, I learned I could not access most of the other computers because they required an account and passwords.   What account and passwords?  I have searched the net and had various solutions suggested, but none of them work.  I also cannot get my homegroups to work, have no idea why that quit working.  I have the same settings I had before the pro came, but can't figure out how to solve the problem of learning the right accounts and passwords.  Any suggestions?