Where are you installing Postfix? While I have yet to upgrade to Catalina (10.15.x), I have done a test of 10.15.4 with no Postfix issues. My Postfix is in /usr/local (built from source - no Homebrew or similar). MacOS upgrades should not be touching /usr/local. I would only expect issues if you installed it in the non-local part of /usr but you should not be able to install Postfix there unless you turned off SIP (System Integrity Protection).
The various problems you are having suggest something very non-standard about your configuration. -- Larry Stone lston...@stonejongleux.com > On Jun 27, 2020, at 5:02 AM, Robert Chalmers (Author) <racu...@gmail.com> > wrote: > > I’m wondering if it’s possible to install Postfix onto the OSX, so that it > doesn’t get overwritten by new updates to the OS every time. I have changed > things a few times but really. There must be a solution. Does anyone have a > useful suggestion? > Thanks > > Robert
