Infrastructure that actually works.
Practical guides on email deliverability, SPF, DKIM, DMARC, server security and managed infrastructure — written by engineers who run it in production.
- email 29 October 2025 4 min read
Why Microsoft 365 DKIM stops signing your email — and how to fix it
Exchange Online DKIM signing can silently stop working after licence changes, domain modifications or tenant reconfigurations. Here's how to detect it and re-enable it.
Read article - email 8 October 2025 5 min read
DMARC's p=none policy does nothing useful — here's what to do instead
A DMARC record with p=none doesn't protect your domain or affect delivery. It just collects reports. Here's how to read those reports and move to enforcement.
Read article - email 24 September 2025 4 min read
The SPF 10-lookup limit: why it breaks email delivery
RFC 7208 limits SPF evaluation to 10 DNS lookups. Exceeding it invalidates your SPF record and causes intermittent delivery failures. Here's how to count your lookups and fix it.
Read article - email 10 September 2025 5 min read
Why your email is going to spam — and how to fix it
SPF, DKIM and DMARC failures account for most email deliverability problems. Here's how to diagnose and fix each one.
Read article
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