When you get an error message it helps to Google the problem. Here are some of the most common error codes.
1. 0x800ccc0d - This error code means that there's a connection problem, it could be due to your firewall or your internet not working. First check that your internet is working and if not, contact your Internet Service Provider.
2. 0x800ccc0e - The following error code means that there's a problem with the settings on your e-mail account, you need to follow the troubleshooting guide on our home page to check that all your settings are correct.
3. 0x800ccc0f - This error code means that your antivirus on your computer is causing problems or blocking your e-mails. Switch off your e-mail protection on your antivirus software and the problem should be resolved. This frequently happens with Avast Antivirus.
4. 550 Relay access denied/ permitted - When receiving this error code, it means that your 'smtp authentication' is not enabled. You need to follow the troubleshooting guide on our home page to make sure your outgoing server (smtp) settings are correct.
6. (0x800CCC80) "None of the authentication methods supported by this client are supported by your server" - To solve this error, change your Outgoing (SMTP) port number to 587 in your e-mail setup.
7. Undelivered email with error: Diagnostic-Code: X-Postfix; Host or domain name not found. Name service error for name=example.co.za type=A: Host not found. - This error means that the email address you are trying to send to does not exist. Check the spelling of the email address and try again. If still undelivered, then the email account has been deleted and no longer exists.
8. Outlook 2016 is not receiving emails - If you have more than one email account set up on your Outlook, both as IMAP, one account receives emails fine, but the other does not, do this to fix the issue: In Outlook, right click on Inbox > In the menu, select IMAP folders > At the bottom of the IMAP folders popup, uncheck the box for "When displaying hierarchy in Outlook, show only subscribed folders."
9. Undelivered email with error: firstname.lastname@example.org> (expanded from <email@example.com>): host alt1.example-smtp-in.l.example.co
For more detailed explanations on Undelivered Email Notifications for sent email, click here