I have an old iMac running 10.10.x and I primarily use it as an external display for a Macbook Pro. I tried to login to the account and got a message saying my password was incorrect. Checked the caps lock and hint and I was using the correct password. I tried another account on the computer and it was incorrect password too. After a couple of attempts all accounts were disabled and I was asked to contact an admin. This is a personal computer so I guess that's me. I'm not a novice so I attempted to get to the bottom of it and seem to have some way bigger issue.
Process to reset passwords as follows. Reset password for the primary Admin account (all accounts but 2 are admin) using iCloud but then the new password was marked as incorrect. I reset computer using
command + R and it loaded Utilities and I changed password using Terminal
resetpassword. I changed all accounts passwords to
1 so that I couldn't miss type.
I reset computer and successfully logged into 2 accounts. I migrated some files and then turned off the screen. After some time, it went to the lock screen. I tried logging in with my password of
1 and the account was automatically disabled after single attempt.
What could the problem be?
Reset Password using Utilities: