Deliverability Academy

Everything that decides whether email lands.

Answer-first guides from the team that runs the RoxInbox network, organised by topic. Each one links to a free tool so you can check your own setup as you read.

Email warm-up

How reputation is built: ramp schedules, network design and what still works.

Pillar guide · 11 min read

The complete guide to email warm-up (2026)

What email warm-up is, how long it takes, whether it still works in 2026 and how to run it safely. Answer-first guide with schedules and tables.

Authentication

SPF, DKIM, DMARC and BIMI, and how to fix the records that break them.

Pillar guide · 12 min read

SPF, DKIM and DMARC explained

What SPF, DKIM and DMARC do, how they work together, and how to set each one up correctly. Record examples, common errors and fixes.

Bulk-sender rules

What large mailbox providers require from senders, and how to meet it.

Pillar guide · 10 min read

Bulk-sender requirements of major mailbox providers

The authentication, unsubscribe and spam-rate rules large mailbox providers enforce on bulk senders, in one checklist. Check your domain free.

Cold email infrastructure

Domains, mailboxes, rotation and sending limits for outbound teams.

Pillar guide · 11 min read

Cold email infrastructure playbook

How to set up domains and mailboxes for cold email: secondary domains, inboxes per domain, rotation, sending limits and warm-up. A practical playbook.

Troubleshooting

Why email lands in spam, and how to find and fix the cause.

Pillar guide · 12 min read

Why are my emails going to spam?

The real reasons emails land in spam, from broken DNS records to blacklists and content, and how to find and fix each one. Run a free check.

Glossary

Short definitions of the terms used across deliverability.