Since switching my personal email over to Sympl, all outgoing emails to domains where Google hosts the email (e.g. gmail.com) are being marked as spam, which effectively means they’re silently deleted. I’ve already made sure the following are in place:
"v=spf1 mx ~all"in DNS (all outgoing mail goes via my MX)
- DKIM: I’ve generated a key and all outgoing mail is being signed, plus I’ve published the DNS record.
- DMARC: I’ve got a basic DMARC record which says don’t take any action (I’m planning to change this to
p=rejectonce I know everything works).
If I view the full email headers in Gmail, I get PASS for SPF, DKIM and DMARC.
I’ve checked various blocklists and it doesn’t look like the IP addresses of the server are listed.
The hostname of the machine resolves to IPv4 and IPv6 addresses, and those addresses match the hostname on a reverse DNS lookup. The same hostname is used as my MX record and I’ve regenerated the TLS certificate so that it comes from LetsEncrypt instead of being self-signed, although I don’t think mail servers are particularly fussy about that.
I’ve run various online tests and the only thing my server gets told off for are:
- Sender and hostname domains are not signed with DNSSEC.
- DMARC policy is
- TLS 1.1 is supported
- DH-2048 key exchange is supported
I don’t know if this is a problem with Sympl or not, but is there anything else I can configure to try and get mail delivered to Google inboxes? Is there a way to disable outgoing mail on IPv6 for example, as I remember Google used to be laxer about checking mail delivered over IPv4?
- Sympl Version: 10.0
- Sympl Testing Version? No
- Debian Version: Buster
- Hardware Type? Virtual
- Hosted On? Mythic Beasts