N.B. this may only work with hosts that don't use UCEProtect and, honestly, if they're legit, they won't use UCEProtect I have two email servers running on Dig

N.B. this may only work with hosts that don't use UCEProtect and, honestly, if they're legit, they won't use UCEProtect I have two email servers running on Digital Ocean just fine - one set up in 2016 and one set up in 2021. It's a matter of doing the initial work to deal with the rejections - following the process the various hosts have set up. There will be a few block lists that you need to submit tickets to to have your IP unblocked. You'll want to create bulk sender accounts (even if you're not) with Yahoo, Microsoft, and Google. It's mostly superstition - "may this web form bring blessings upon my IP". Don't bother actually trying to check any of the reports in the UIs - only Yahoo sends emails to abuse@ for spam reports for small senders. You'll want to join the Mailop list [0]. I'd say it takes about a month or two, mostly spent waiting, before you are in the clear and have perfect deliverability. Yes, it's annoying. Yes, it can feel hopeless. But it clears up pretty quickly. I've only since had problems with smaller providers and it usually gets resolved by contacting them. [0]: https://www.mailop.org/ https://www.mailop.org/ - I think people who work at Yahoo, Google, and Microsoft all monitor this list