> Many corp email smtp servers will IP block your email server (big thanks to spamhaus) Nope. Spamhaus doesn't block self-hosted email servers. Spamhaus just

> Many corp email smtp servers will IP block your email server (big thanks to spamhaus) Nope. Spamhaus doesn't block self-hosted email servers. Spamhaus just publishes a number of lists, which postmasters can use or not, whether for filtering or just for scoring. The PBL in particular is likely to catch people self-hosting from a retail connection, because it lists most residential IP address-space. But it's the receiving mailserver that does the blocking, not Spamhaus. And it's down to the policies of the receiver's postmaster what lists are used and how they are used. That requires judgement and research, and some postmasters lack the former or don't have time for the latter.