Which means your /etc/passwd is either changed or damaged.
You could do some open heart surgery by putting the SD card into your PC and edit cmdline.txt and set init=/bin/bash
and then boot it into a root shell.
Than you could first check the /etc/passwd file, if it looks ok just use passwd osmc to reset the password.
But you might actually still need to figure out what happen which could be:
Someone got hold of your device and changed the password
You have file corruption which would indicate a failing SD Card
As far as I understand, after setting init=/bin/bash into my cmdline.txt, it should boot into a root shell immediately. But although I set it, it boots into Kodi as usual.
Well as mentioned you might still want to figure out what happen.
Because it is for sure not normal that it happen and must be related to one of the two points I mentioned.
I have the same issue since the last update, and let me tell you that it’s for sure an abnormal behavior.
Let me explain how and why:
Today I rebooted via SSH remote console (via putty).
Result: after the Pi came up again my OSMC user and password did not work anymore - “Access denied”
I rebooted the Pi once more - it worked again.
Another reboot - same as before - Access denied.
Another reboot - Access denied
Now I am trying to reboot for the 4th time in a row, and still my user and password are not accepted anymore.
What the heck is going on here?? And how do I get back to my console now?
Is there still any root account or something? I renamed mine and only work with that one, which is the one which shows that weird behavior now.
I just unplugged the power and then plugged in again. Before booting up it said:
“Waiting for root file system - recovering journal” => is that a hint that my memory card might in fact have an issue?