Trying to restart Dovecot and getting “Fatal: Dovecot is already running? Socket already exists: /var/run/dovecot/login/login”?

Then open a console and end (kill) all processes by running this:

for i in `ps aux | grep dovecot | awk '{print $2}'` ; do kill -9 $i ; done

… then:

service dovecot restart

.. and done, problem solved! 🙂