Can't log in after update -password incorrect [Solved]

[denijane]

Yesterday I updated the sudo trough Spritz and today, I can't log in. At all. What's weird is that I logged in once and when I tried to run knetworkmanager, it told me that my user isn't in the sudoers file. So, I went on to check the sudoers file and when I wanted to edit it, it stopped accepting my password, didn't want to open anything (with "can't open display" error) and from then on, I cannot log in. Not like user, not like root. I can't log trough console neither /tells me my password is incorrect/.
So what should I do to make my users usable again? I sincerely hope there is a way other than reinstalling.

[Fitzcarraldo]

You could try Recovering the root password

[denijane]

Hey, thanks for the link.
I tried that but I have some troubles working in that mode-can't nano or stuff. Maybe I did something wrong.
Anyway, I loaded my old live dvd of SL4 and used
sudo chroot /media/disk/
passwd myuser
and everything is working again. Nice
Ok, I'm still not in the sudoers file, obviously, but that will soon change Have a nice day. (And yet, maybe that update shouldn't have messed up with my permissions, right?)