substack.com

Checked 5/14/2026, 10:49:13 PM · 5ms

Solid: p=reject is enforced.

DMARC record

v=DMARC1; p=reject; pct=100; rua=mailto:[email protected]; sp=reject; aspf=r;

Policy (p): reject
Subdomain policy (sp): reject
Enforcement % (pct): 100%
DKIM alignment (adkim): unset · defaults to r (relaxed)
SPF alignment (aspf): r (relaxed)
Aggregate reports (rua): mailto:[email protected]
Failure reports (ruf): none

All tags (6)

vDMARC1DMARC version
prejectPolicy for the domain
pct100Percentage of mail subject to policy (0-100)
ruamailto:[email protected]Aggregate report URIs
sprejectPolicy for subdomains
aspfr (relaxed)SPF alignment mode

SPF record

Found on the apex domain.

v=spf1 include:_spf.google.com include:mailgun.org include:mail.zendesk.com ~all

Recommendations

DKIM alignment (adkim) is unset, so it defaults to r (relaxed). That is fine for most deployments. Set adkim=s explicitly only if your DKIM d= header matches the From: domain exactly.
aspf=r (relaxed) is fine for most deployments. Consider aspf=s only if your Return-Path aligns with the From: domain exactly.

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