I've run a ClearOS system for many years. Recently I decided to change from a gateway to a standalone mail server after installing some new network equipment. With the system in standalone without firewall mode, NIC routed to external, and the additional NICs disabled, the system has stopped retrieving messages. I have more than 80 backed up at Clear Center. This also happened while the system was still in gateway mode, fixed it by retrieving a back up from several days prior. I don't know what caused the issue, but going back several days fixed it. That isn't going to work this time, as it will return the system to gateway mode and conflict with the new Unifi gateway. I went so far as to set up another computer with the Free version, and it will not retrieve mail either. I had to open a new account on this forum as my prior one is linked to my primary email, which I cannot access. Any possible help would be greatly appreciated. The standalone system is set up as mail.wa4rts.net for both categories, and the domain is wa4rts.net. I redid the security certificate to reflect the new names and did the same in DNS entries. I can login via the GUI and all settings seem to be correct. End of the rope, I can't figure out what's wrong. Thanks.