New laptop, first time Win10.

I'm not yet ready to deal with the frustration of trying to setup a 'real' network with the other 2 machines so I'm doing a Homegroup temporarily. When prompted for the password, I opened Homegroup on my old Win7 machine and carefully typed the (case sensitive) password that the Win7 machine displayed. The sign in failed. The 'name' was already filled in as 'mark' and that's what is displayed under Users. I have quadrupled checked the password that I entered and it is identical to that displayed on the Win7 machine?