Emails going to spam: how to find the cause and fix it

What is happening

Customers say your quotes and invoices are in their spam folder, or replies never arrive. Mail providers such as Gmail and Outlook score every message on three things: whether it is authenticated (SPF, DKIM, DMARC), what the content looks like, and the reputation of the sending server and your domain. This article helps you find which one is failing. For full setup of the records, read our SPF, DKIM and DMARC guide.

Step 1: read the headers of a test message

1. Send a plain test email from your business address to a personal Gmail account.
2. Open it in Gmail on a computer, click the three dots menu and choose Show original.
3. Read the summary at the top. You want SPF: PASS, DKIM: PASS and DMARC: PASS. Any FAIL, SOFTFAIL or NONE points to the step below.

Outlook.com shows similar results in the message source under Authentication-Results.

Step 2: fix authentication

1. Open Email > Email Deliverability in cPanel (menus vary by version and host configuration). It checks your domain's SPF and DKIM records and can suggest the right values. If your DNS is hosted elsewhere, copy the suggested records to that DNS provider.

2. Keep only one SPF record. It must include every service that sends as your domain: your hosting server, Google Workspace or Microsoft 365, your billing software, your newsletter tool. For example:

   yourbusiness.in.  3600  IN  TXT  "v=spf1 +a +mx include:_spf.provider.example ~all"
   

   SPF allows at most 10 DNS lookups; too many include: entries make the whole record fail.

3. Enable DKIM for the domain and confirm the public key TXT record is published.

4. Add a DMARC record, starting in monitoring mode:

   _dmarc.yourbusiness.in.  3600  IN  TXT  "v=DMARC1; p=none; rua=mailto:dmarc@yourbusiness.in"
   

   Move to p=quarantine only after reports show all your legitimate mail passes.

5. Wait for DNS to update (see DNS propagation) and send a new test.

Step 3: check content and sending habits

1. Avoid link shorteners, all image emails, attachments with macros, and subject lines in capitals or full of offers.
2. Match the visible "From" name and address to your real business, and send from your own domain rather than a free mailbox.
3. Send to people who expect your mail. Purchased lists and old addresses lead to bounces and spam complaints, both of which damage reputation.
4. Follow Google's sender guidelines if you send to many Gmail users: authenticate, make unsubscribing easy and keep the spam complaint rate low.
5. Use a dedicated email marketing service for newsletters instead of your hosting mailbox, and ask support about any sending limits on your plan.

Step 4: check reputation

1. Search your domain and the sending IP (from the Received lines in the headers) on a public blocklist checker.
2. Check for compromised mailboxes. Sudden bounces from addresses you never wrote to usually mean a password was stolen. Change it and turn on stronger security; see securing your hosting account.
3. Ask regular contacts to add your address to their contacts and mark messages "Not spam".

How to confirm it worked

• Show original in Gmail shows SPF, DKIM and DMARC all as PASS.
• New test messages land in the inbox at Gmail and Outlook.com.
• DMARC reports, if you added an rua address, show your sending sources passing.

If it still fails

If authentication passes but mail still goes to spam, or the server IP is on a blocklist, open a support ticket with:

• The sending address and one or two recipient domains affected
• The full headers of a message that went to spam (from Show original)
• Your current SPF, DKIM and DMARC records
• Roughly how many emails you send per day and what kind
• Any blocklist name that lists your IP or domain

For mailbox plans, see ODHOST email hosting.