Cannot change user email \ FTP password in Virtualmin Pro

I'm trying to change a users password in Virtualmin. It sits there and does nothing for 5 minutes, then I get the error:

Failed to lock file /etc/passwd after 5 minutes



If you run "ls -a /etc/*.lock", do you see any results?

after making the above changes I get a different error:

Failed to lock file /etc/security/limits.conf after 5 minutes

Did you by chance perform any updates on your server recently? Do you recall what packages were updated?

You can determine what all dpkg installed by looking in /var/log/dpkg.log.

Those locking failures can happen if a .lock file exists, but is empty. Normally they contain a process ID, which Webmin uses to check if the original locker is still running .. but an empty .lock file cannot be validated in this way. Some other programs like vipw create an empty /etc/passwd.lock file.

What is the contents of these .lock files? If it is a PID, what is the command line of that process?