Can I use IPv6 port 25 outgoing on DigitalOcean? Cody Selzer April 16, 2021 01:25 Updated Question Can I use IPv6 port 25 outgoing on DigitalOcean? Answer No, IPv6 connections outgoing on port 25 are blocked network-wide. More details here: https://ideas.digitalocean.com/ideas/DO-I-1366 Related articles How To Send Email When Your Server Provider Blocks Port 25 Why is port 25 blocked? The IP you're using to send mail is not authorized to send email directly to our servers. cPanel DNS Cluster Guide How do I change my Exim SMTP port from 25? Comments 0 comments Article is closed for comments.