I installed a fresh 16.04 on a Lenovo Ideapad 300 i5 Skylake.
During installation I entered a user name and password. The installation concluded fine and asked me to reboot. Did the reboot. Got to the login screen, wrote the password and the system responds that it's wrong.
I installed again, this time making absolutely sure there were no password errors. Same thing.
I installed yet again, this time tagging off the password at login, entered the system and all was well but the problem persisted. In terminal when I tried to execute a sudo command, the password I know for a fact is right, turned out wrong.
What is going on? Is there a default password that I'm not aware of?