I'm trying to add a user (as root) on CentOS 5.5 and I've got this message :

useradd: unable to lock password file

After reading some post linked to this issue I've deleted two files in /etc :

• .pwd.lock
• passwd-

However it still doesn't work. Finally, I read a thread where the guy said that using the passwd command to update the passwd file and normally fix this issue. I've tried with the root user But I've got this issue :

passwd: Authentication token manipulation error

Any idea to add my user ?