I have 2 computers, a desktop computer and a laptop. Both have a dual boot, with Windows 10 and Ubuntu 19.10.
My printer is a Xerox WorkCentre 6015B.
Everything worked well with Ubuntu 19.04 and before also (I use Ubuntu since 12.04). I configure exactly the same way on both computers and now I get the same error message on both computers saying:
Requires authentication / Credentials required in order to print.
The printer works with Windows 10, so I think there is not a problem with the printer. I created a live USB with Ubuntu 19.04, and I can configure the printer and I can print. So this comes from Ubuntu 19.10 I believe.
The error message says "requires authentication", but I don't know which username or password I need and where to put them. Before Ubuntu never asked me to authenticate. Do you think it could be a bug? Have any of you encountered the same problem?