I was hopefully a returnee to Mageia after a gap of two years.
I downloaded the 7.1 ISO, burned it to a DVD and made a four)clean install.
I naively expected the install process to be as easy as it used to be.
I did not expect the grub boot-loader password question and tried the root password.
On the restart it could not log-in and it froze at the "Welcome to localhost" dialog.
I then did a second install but carefully watched each stage but achieved nothing new.
After the third installation I booted into the rescue option and got to the root prompt
and executed startx. This produced a desktop but I could not open the MCC.
Mageia was also unable to "see" my second screen.
On the fourth reinstall I entered no password at the grub boot-loader screen.
That did not improve matters.
I did report these events on the Mageia newsgroup but they appear to be unique.
I decided to seek some suggestions before giving up completely.