Yes, Microsoft blocked me sending email from my shared hosting to my Hotmail. The email address was whitelisted, and established email back and forth to that domain, and no spam ... but another server at the same host had previously been blacklisted in one blacklist.

SPF nor DKIM helped, I don't own the mail server nor want to pay Microsoft's service provider to verify me.

In the end I had to bounce the emails from a third-party address. Which you'd think shouldn't work -- certainly not when whitelisting doesn't -- but solved the problem.

So to avoid being flagged as a spammer, do the spammiest thing possible: set up a new, free mailbox and bounce your mail from there. SMH.