Even the best content lands in spam without proper domain authentication. Five fundamentals every B2B sender must get right.
1. SPF record
SPF (Sender Policy Framework) is a DNS TXT record listing which servers are allowed to send for your domain. If you use Gmail Workspace, Microsoft 365 or SMTP relays, include them all. A missing or misconfigured SPF is the #1 deliverability killer.
2. DKIM signature
DKIM (DomainKeys Identified Mail) cryptographically signs outgoing emails. Receivers verify the signature against your DNS public key. Without DKIM, your emails look unauthenticated and Gmail/Outlook will route them to Promotions or Spam.
3. DMARC policy
DMARC (Domain-based Message Authentication) tells receivers what to do when SPF/DKIM fail. Start with p=none for monitoring, advance to p=quarantine, finally p=reject. DMARC also gives you reports on who tries to spoof your domain.
4. Warm up new sending IPs and addresses
Sending 5,000 emails on day 1 from a fresh IP is the fastest way to get blocked. Start small (50-100/day), grow daily, watch bounce and complaint rates.
5. Hygiene
- Never email scraped lists — your reputation will tank in days.
- Honor unsubscribes immediately. OMB Cloud handles this automatically across all outbound modules.
- Bounces: hard-bounce addresses are auto-suppressed after one failure. Don't try to "fix" them by re-sending.