[jmb99]

I’ve been running a personal mail server since 2016, and I’ve been struggling mostly with Microsoft off-and-on. I haven’t make any changes since setting up DMARC, SPK, and DKIM in 2016, but I’ll still sometimes randomly get blacklisted for 2~30 weeks for seemingly no reason, and then get unblocked again for seemingly no reason.

It’s recently started happening with iCloud too. For 5.5 weeks any email I sent would either get bounced or land straight in Junk, until yesterday when the powers that be decided my mail was worth delivering again.

I’ve somehow never had an issue with Gmail or Yahoo, and of course never with any other non-big-three mail servers.

[dugite-code]

Could be your IP block gets the odd spammer or you don't send enough emails and their servers resets you IP address reputation, meaning you essentially become a new email server.