I have a specific scenario, but I wanted to understand how to troubleshoot this generally.
I have a debian machine, with lighttpd and egroupware installed (egroupware installed via an OpenSUSE repository).
I want to install roundcube on this machine, and if I try, apt tells me it will uninstall all of the egroupware packages.
I think it must be that roundcube will bring in a dependency that conflicts with a dependency that egroupware needs. So to satisfy roundcubes requiremnts, the egroupware dependency must be removed, and so egroupware itself must be removed.
My question is - how can I identify the conflict easily? I figure I can work out the dependencies of both, and go though them one by one, but I am hoping there is an easier way to get apt to reveal its decision making process.