I’m using Virtualmin GLP for more than a year without problem but just after the last update I had to install a certificate for one of my domains. After install a second IP and the cert following Virtualin GLP Documentation the Postfix Mail Server stopped to work and cannot be started again.
After try to find the reason for the troubles with mail I created an Issue (Support request) that was answered in the same day by andreychek:

[code]Howdy – the errors you’re getting in Webmin may indicate that there’s a problem with the SSL certificates that were installed.

The error in Postfix may indicate a problem with the file.

We can help, though since you appear to be using Virtualmin GPL there, the best place to get support for that would be in the Forums (which we monitor as well, along with lots of wonderful folks in the community).

When posting a new Forum thread, could you include the contents of your /etc/postfix/ file? We can then review that to figure out if there’s an issue with it.

Of course, if any of them ends up being a Virtualmin bug, we’ll get Jamie involved and make sure it gets fixed up.

Posted by andreychek on Wed, 2015-06-17 11:37
So I did create an entry in this forum (“After Cert Install problems with Postfix”) in the same day last week but until today so far the answers are equal to NONE !
I have more than 2,000 emails waiting in the “Mail Queue”, some very angry clients calling everyday and don’t know what to do! I read every entry related to Virtualmin/Postfix I could find in this forum and tried dozens of solutions that I read about those problems but could not find the answer!

What do I need to do to have some basic support for Virtualmin GLP?

@telirup8: First you must understand that only 3 people sit behind Virtualmin and sometimes they could be little short with their time. On other hand the community is not big and all comes down to few people who will occasionally jump on forum and try to help others. If you are using Virtualmin for business then i would suggest to go for Pro version and get little more attention or if you really need fast support in removing all problems then managed server (VPS or Dedi) with cPanel - right now in terms of support speed nothing can beat that. For Virtualmin GPL you have two options, your knowledge so you can sort the problem by yourself or patience what in case of selling your service to others is not good choice, e.g. clients hate to wait.