Have a dining table companion at our assisted living home who said just tonight that he has a MacBook Pro but is not able to use it. I asked him why, and he said that he installed a new OS update some years ago which then required an administrative password for him to start the computer. But, the update did not provide him the password, hence he now has a MacBook Pro that does not function. This was a off-the-wall conversation, so he was not able to go into much detail immediately. He thinks maybe the MacBook Pro was a 2012ish model, and thinks maybe he was switching to something like Sierra at the time. I know virtually nothing about administrative passwords. I do have a 2015 MacBook Air which came with Yosemite, as I recall, and which I have updated successively through Catalina so far. Never have I been required to have an administrative password. Provided he is willing, I will try to get some more specific information, like model and OS, but to ask him intelligent questions, does anyone have any ideas as to what may have happened?