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Email Troubleshooting Guide

This guide covers common email problems and how to resolve them.

Issue: Not Receiving Emails

Check These First

  • Check spam/junk folder
  • Verify mailbox is not full (check quota in cPanel)
  • Confirm MX records point to correct server
  • Test by sending from external email (Gmail)

Check MX Records

  1. Go to cPanel > Zone Editor
  2. Look for MX records
  3. Should point to your mail server (e.g., mail.yourdomain.com)

Check Email Routing

  1. Go to cPanel > Email Routing
  2. Ensure set to Local Mail Exchanger

Issue: Cannot Send Emails

From Webmail

  • Check you are logged in correctly
  • Verify recipient address is valid
  • Check for any error messages

From Email Client

  • Verify SMTP settings are correct
  • Ensure authentication is enabled
  • Try port 587 with STARTTLS
  • Check username is full email address

Issue: Emails Going to Spam

For Outgoing Emails

  • Check SPF record is configured
  • Enable DKIM signing
  • Add DMARC record
  • Check server IP is not blacklisted
  • Avoid spam trigger words in subject/body

Check Blacklist Status

Use MXToolbox Blacklist Check to see if your IP is listed.

Issue: Login Failed

  • Verify using full email address as username
  • Check password is correct (case-sensitive)
  • Reset password in cPanel if unsure
  • Check account is not suspended

Issue: Certificate Warning

When connecting via email client:

  • Use mail.yourdomain.com as server (not server hostname)
  • Or accept the certificate warning
  • Ensure SSL/TLS is enabled with correct ports

Issue: Emails Bouncing Back

Read the Bounce Message

Common bounce reasons:

Error Meaning Solution
550 User not found Recipient does not exist Verify email address
552 Mailbox full Recipient quota exceeded Contact recipient
554 Blocked Your server is blacklisted Check blacklists
421 Too many connections Sending too fast Slow down sending rate

Issue: Slow Email Delivery

  • Check server load and resources
  • Review email queue in WHM (contact support)
  • Large attachments slow delivery
  • Receiving server may be slow

Issue: Missing Old Emails

  • Check Trash and Spam folders
  • If using POP3, emails may be on local computer only
  • Check webmail for server-side copies
  • Contact support about restoring from backup

Useful Diagnostic Tools

  • Email Trace: cPanel > Track Delivery
  • Mail Logs: Contact support for server logs
  • MXToolbox - DNS and email diagnostics
  • Mail-Tester - Email quality score

When to Contact Support

  • Server-level email issues
  • Blacklist removal requests
  • Email restoration from backup
  • MX record or DNS issues
  • Persistent delivery problems