First, I want to thank Falko for the How To and ISPConfig. I am quite sure you've spent a lot of time, energy, and emotion here. I cannot do what you do, and I appreciate the opportunity to try and use this freely shared knowlege of yours.
I'm sure that I'll get booed for what comes next.
I've spent 6 days trying to get ISPconfig top work on a brand new fresh install following the perfect hot to for Core 4. The mail deal is broken. Just broken.
I remove postfix, I remove all certs, remove /etc/postfix, reinstal postfix, rebuild certs per hos to, rebuild postfix main.cf from scratch (per the perfect install). Every time I rebuild (well over 20 times), I get a message that the certificates are invalid (8182), and then I follow the rebuilding. Every time.
After this, I can send mails to addresses I've created from other domains, I can see them delivered, I can see them forwarded. I can't, however, send mail remotely with an email client (and for the last thre or four installs can't even get mail remotely), which is the only reason I need to install ISP Config. I can handle web no problem, and mail in a LAN environment. I've not been able to get SMTP AUTH to work, ever, and I've tried ISPConfig for this.
Users cannot log into the https://domain.com:81/mailuser
cannot be found...What? I have no idea why not. I swear to god I am not trying to rant, but looking back, I had to solve mail looping back, I had issues with CTX (no idea), and errors such as:
451 Server configuration error
Unable to load certificate from /usr/share/ssl/certs/ipop3d.pem
I've actually been fired from the job, which isn't surprising: I couldn't deliver. I still want to try and figure this out. Why am I reading about certs that aren't referenced in the perfect setup or ispconfig?