How do I troubleshoot common email delivery issues?

Possible Causes and Solutions:

1. Incorrect SMTP Settings
   • Solution: Verify your outgoing server settings:
     • Server: mail.yourdomain.com
     • Port: 587 (with STARTTLS) or 465 (with SSL/TLS)
     • Authentication: Required
     • Username: Your full email address
     • Password: Your email account password
2. Authentication Failures
   • Solution: Double-check your username (full email address) and password. Reset your email password in cPanel if necessary.
3. Port Blocking by ISP
   • Solution: Some ISPs block email ports. Try alternative ports:
     • If port 587 doesn't work, try port 465 or vice versa
     • Contact your ISP to see if they block email ports
4. Sending Limit Reached
   • Solution: Check if you've hit hourly sending limits (typically 500 emails per hour). Wait and try again later, or spread out mass emails.
5. SSL/TLS Certificate Issues
   • Solution: Make sure your email client is configured to accept the server's SSL certificate. Update your email client if it's outdated.

Possible Causes and Solutions:

1. Mailbox Full
   • Solution: Check your email quota and clear space if needed:
     • In cPanel, go to Email Accounts to check your usage
     • Delete unwanted emails, especially from Trash and Spam folders
     • Archive old emails to your computer
2. Incorrect MX Records
   • Solution: Verify your domain's MX records:
     • In cPanel, go to Zone Editor
     • Check that MX records point to your domain's mail server
     • Default should be: mail.yourdomain.com
3. DNS Propagation
   • Solution: If you recently changed DNS settings, wait 24-48 hours for propagation to complete.
4. Incoming Mail Filtering
   • Solution: Check your spam filters and email rules:
     • Look in Spam/Junk folders for missing emails
     • Review email filters in cPanel that might be redirecting messages
     • Whitelist important senders in SpamAssassin
5. POP3/IMAP Configuration
   • Solution: Verify incoming mail settings:
     • IMAP: mail.yourdomain.com:993 (SSL/TLS)
     • POP3: mail.yourdomain.com:995 (SSL/TLS)
     • Username: Your full email address
     • Authentication: Required

Possible Causes and Solutions:

1. Invalid Recipient Address
   • Solution: Double-check the email address for typos.
2. Recipient Mailbox Full
   • Solution: Ask the recipient to clear space in their mailbox.
3. Your Domain is Blacklisted
   • Solution:
     • Check blacklist status at MXToolbox
     • Follow delist instructions if your domain is blacklisted
     • Contact our support team for assistance with blacklist removal
4. SPF, DKIM, or DMARC Issues
   • Solution: Set up proper email authentication:
     • Add SPF record: v=spf1 a mx ip4:YOUR_SERVER_IP ~all
     • Set up DKIM through cPanel's Email Authentication
     • Add DMARC record to strengthen delivery
5. Content Triggers Spam Filters
   • Solution: Modify email content:
     • Reduce excessive capitalization and exclamation points
     • Avoid spam trigger words like "free", "guarantee", etc.
     • Balance image-to-text ratio
     • Include proper unsubscribe options in marketing emails

Possible Causes and Solutions:

1. Missing Email Authentication
   • Solution: Implement proper email authentication:
     • SPF records verify your sending server is authorized
     • DKIM adds a digital signature to your emails
     • DMARC sets a policy for handling authentication failures
2. Poor Sender Reputation
   • Solution: Improve your sending practices:
     • Send emails only to people who have opted in
     • Keep your email list clean by removing bounces
     • Send consistent volumes (avoid sudden large batches)
3. Content Issues
   • Solution: Improve your content:
     • Maintain a good text-to-image ratio
     • Avoid excessive links
     • Don't use URL shorteners for important links
     • Proofread for spelling and grammar
4. Recipient Settings
   • Solution: Ask recipients to:
     • Add your email address to their contacts/address book
     • Mark your emails as "Not Spam" if found in junk folder
     • Create a filter/rule to ensure delivery to inbox

Possible Causes and Solutions:

1. Server Load
   • Solution: If delays happen during high-volume sending, spread out your sending times or contact support about dedicated email resources.
2. Greylisting
   • Solution: Some receiving servers use greylisting (temporary rejection of new senders). Subsequent delivery attempts will succeed automatically. This usually resolves within 10-15 minutes.
3. Email Size
   • Solution: Reduce attachment sizes or use links to files instead of attachments.
4. DNS Issues
   • Solution: Check that your domain's DNS records are properly configured, especially MX records.
5. Recipient Server Issues
   • Solution: If delays only affect certain domains, the issue might be with the recipient's mail server. Try contacting them directly.