By Zain Ul Abddin.
Your domain's SPF record must include the sending server. In cPanel: Email Deliverability → check SPF validity. One typo here and Gmail files everything under Promotions — or worse.
Enable DKIM signing in cPanel so receivers can verify mail actually came from you. Unsigned mail from a shared server is guilty until proven innocent.
Even v=DMARC1; p=none; rua=mailto:you@domain.com helps: you get aggregate reports showing who sends as your domain, including abusers.
The sending IP needs a matching PTR record, and the IP must not sit on blacklists. This is exactly why our hosting includes 150/hr inbox-tuned delivery instead of raw port-25 access.
150 emails/hour on our Business plans is generous — but blasting a 10,000-address list from shared hosting will still get throttled. Use a proper list service for bulk; use hosting mail for transactional mail.
Email failing despite all five? Send us a bounced header — deliverability debugging is included support.
