Hi guys. I'm having problems receiving emails they simply don't arrive. The sender does not get any errors or mail returned. I've tried to send an email to myself using the same domain and that sends but not returns. I'm using Roundcube and I have tried Outlook 2016 set up as IMAP I'm behind a router and have checked the firewall and port forwarding is ok. I've checked the firewall in ispconfig and the ports are open and forwarding as well. DNS checks out and as far as I can tell the mx records and cnames are all fine. I've spent a few days looking for a solution in the hope that I didn't need to bother anyone... but now I've drawn a blank. If anyone can help I'd be delighted. I've attached the mail log and also the master.cf in the hope that it helps.