meekish@server:~$ sudo apt-get install courier-authmysql courier-pop courier-imap Reading Package Lists... Done Building Dependency Tree... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: courier-authmysql: Depends: courier-base (>= 0.47) but it is not going to be installed Depends: courier-authdaemon (>= 0.47) but it is not going to be installed courier-imap: Depends: courier-base (>= 0.53.2) but it is not going to be installed courier-pop: Depends: courier-base (>= 0.53.2) but it is not going to be installed E: Broken packages meekish@server:~$ sudo dpkg -l "*courier*" Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed |/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad) ||/ Name Version Description +++-========================-========================-================================================================ ii courier-authdaemon 0.58-3 Courier authentication daemon ii courier-authlib 0.58-3 Courier authentication library ii courier-authlib-userdb 0.58-3 userdb support for the Courier authentication library un courier-authmysql (no description available) un courier-authpostgresql (no description available) ii courier-base 0.53.2-3 Courier Mail Server - Base system un courier-debug (no description available) un courier-imap (no description available) un courier-mta (no description available)