There is a topic that brings up this issue, but not as the main topic. I was trying to upgrade OpenChange to 3.4.1 and it failed because it was looking for Zentyal-Mail 3.4.1. In effort to try get the system to work (new system) I removed the mail module and attempted to reinstall it. However, the mail module is now not showing up on the components list. I tried to manually apt-get install Zentyal-Mail and it states that there is no installation candidate. How do I get my mail system back?