Originally Posted by theNbomr
AFAIK, you can simply modify /etc/passwd as appropriate, and any new logins for the respective use will assume the new ID. You probably want to make the accordant change in /etc/group, as well. Any files that are owned by an abandoned UID can be chowned as necessary. Existing logins may misbehave if file permissions change in unexpected ways.
I have encountered the same issue, and fixed the problem as described.
Unfortunately this didn't go well. After updating /etc/passwd and /etc/group, and chowning my home dir, I was unable to log in.
As the services are getting initialised at boot time, I get the following error message repeatedly:
Unknown username "root" in message bus configuration file
Could not get password database information for UID of current process: User "???" unknown or no memory to allocate password entry
Eventually the message stops repeating and ends with:
Failed to start message bus: Could not get UID and GID for username "dbus" [FAILED]
Then most of the remaining services start successfully, apart from Avahi, which says [FAILED] but gives no error message.
Then after waiting several minutes with no messages, X fails to start and I'm presented with a text logon screen, but I can't login with either my normal username or root, it just gives the error message "Login incorrect".
I've now reverted /etc/passwd and /etc/shadow to their previous contents, but get exactly the same errors.
I checked there were no conflicts with another user/group having id 1000. The entries for the dbus user in the various files are
/etc/passwd: dbus:x:81:81:System message bus:/:/sbin/nologin
I'm not sure if that's problematic - my understanding is that a disabled account has "*" in the password field, not "!!". Googling
for the first line of my error message, I found one hit
where somebody got the same message after updating /etc/passwd, but it relates to changing passwords, which I haven't done, and the suggestion to change a password using passwd
seems unlikely to do anything in my situation.
Does anyone have any suggestions? I do have a recent backup of the system partition, but would prefer not to use it if possible as I've just downloaded > 1GB of package updates.