I have self-hosted my mailserver for a long time and started to get problems a couple of years ago. The main issue is corporate networks running McAfee's "MxLo

I have self-hosted my mailserver for a long time and started to get problems a couple of years ago. The main issue is corporate networks running McAfee's "MxLogic" product that claim to bounce my mail and tell me so, but then go on to deliver it almost all the time. The difficulty in getting feedback is extremely frustrating, particularly compared with getting feedback from, eg, google's webcrawlers.