Testing That All Necessary Services Are On

You can check by executing

service foo status

If a service is running, it should give you a PID number of the service.
A common issue is when cyrus-imapd fails to start. The output generated is

Starting cyrus-imapd: preparing databases... FAILED!

That usually is a result of a corrupted database file at build, specifically mailboxes.db or annotations.db in the /var/lib/imap directory. Rename them to a backup filename and then restart the service. Cyrus should create new working database files and the service should start with no problems.