Troubleshooting Guide: Third-Party Email Client Issues

(Outlook, Apple Mail, Thunderbird, iPhone, Android)

This guide helps diagnose and fix the most common email errors when connecting through IMAP or POP3.

1. Basic Checks First

Before diving deeper:

Tip: Try logging into Webmail to confirm the account works.

2. Confirm Correct Email Settings

Most hosting providers use these common settings:

Ensure that you use the same settings as the incoming mail server is configured for SMTP authentication.

3. Incorrect SSL/TLS or Security Settings

Symptoms

• Connection errors like:
  “Cannot verify server identity”
  “Certificate not trusted”

Fixes

• Select SSL/TLS encryption if supported

• Accept/Trust certificate if prompted

• If SSL issues persist, test using non-SSL temporarily

  • IMAP 143

  • SMTP 587

4. Outgoing Mail Not Sending (SMTP Errors)

Symptoms

• Emails stuck in Outbox

• Errors like:
  “Relay access denied”
  “Cannot send message”

Fixes

5. Login Errors (Authentication Failed)

Symptoms

• Password always rejected

• “Wrong password” in the client, but it works in Webmail

Fixes

• Confirm the full email address used as a username

• Reset email password in the Eclipse portal

• Remove and re-add the email account if the client has cached outdated credentials

6. Unable to View or Sync Some Emails (IMAP Issues)

Symptoms

• Missing folders

• Emails appear only on one device

Fixes

• Ensure account is set up as IMAP, not POP3

• Synchronise IMAP folders in client settings

• Increase IMAP folder size limits (in settings)

• Click Subscribe to missing folders (Thunderbird/Outlook)

7. Mailbox Full / Quota Exceeded

Symptoms

• Cannot send or receive new emails

• Mail bounce messages saying “over quota”

Fixes

• Portal → Email Accounts → Increase quota

• Delete old emails or empty Trash/Junk folders

• Avoid downloading duplicates if using POP3

8. DNS / Propagation Problems

Symptoms

• Works on one connection, not another

• New domain setup issues

Fixes

• Check the correct DNS MX records pointing to your server

• Use the server hostname instead of the domain temporarily

• Allow up to 24 hours after DNS changes

9. Spam or Blacklist Issues

Symptoms

• Sent messages end up in spam or bounce back

Fixes

• Ensure SPF, DKIM, and DMARC are correctly configured in DNS

• Avoid using public Wi-Fi with blocked SMTP

• Check the server IP reputation with hosting support

10. Mobile Device Issues

Fixes

• Remove and re-add the account with IMAP

• Reset network settings (mobile)

• Ensure background sync is allowed