Outlook shows an error code when it can’t send or receive email. This guide explains what the most common codes mean and the steps to fix them.
Before you start
Note the exact error code Outlook displays. You’ll need it to work out the cause, and to give our support team if you get in touch.
Check your email account settings
- Open Outlook and click File.
- Click Account Settings, then Account Settings again.
- Select your DomainsFoundry email account and click Change.
- Check the server name and username. The server name is mail.yourdomain.com, where
yourdomain.comis your own domain. Your username is your full email address, for exampleinfo@example.com. - Check the ports and encryption against the table below.
- Check My outgoing server (SMTP) requires authentication is ticked, using the same details as your incoming server.
| Setting | Value |
|---|---|
| Incoming (IMAP) | Port 993, SSL/TLS |
| Incoming (POP3) | Port 995, SSL/TLS |
| Outgoing (SMTP) | Port 465, SSL/TLS |
For full instructions, see How to check your incoming and outgoing mail servers.
Check your password
- Sign in to DomainsFoundry Webmail
- If you can sign in, your password is correct. If not, reset it.
Check your internet connection
Open a web page in your browser to confirm you’re online. A weak connection can cause time-out errors.
Restart Outlook and your computer
- Close Outlook completely.
- Restart your computer.
- Open Outlook and try to send or receive again.
Check your firewall or antivirus
Security software can block the ports Outlook uses. Temporarily disable it, try again, then turn it back on.
Common Outlook error codes
| Error code | What it means | What to try |
|---|---|---|
| 0x80040900 | Outlook can’t find the mail server | Check the server name is spelled correctly |
| 0x80042108 | Can’t connect to the incoming (POP3) server | Check incoming server settings and internet connection |
| 0x8004210B | The incoming (POP3) server timed out | Check internet connection and firewall |
| 0x800CCC0E | Can’t connect to the mail server | Check server settings and firewall |
| 0x800CCC0B | A time-out occurred while talking to the server | Check internet connection, restart Outlook |
| 0x800CCC15 | The server ended the connection unexpectedly | Check firewall and server settings |
| 0x800CCC79 | The outgoing (SMTP) server refused to send | Enable SMTP authentication in account settings |
| 0x800CCC67 | The server is busy | Wait a few minutes and try again |
| 0x800CCC81 | Authentication failed | Check your username and password |
Still stuck?
If the error continues, contact DomainsFoundry support and tell us the exact error code. It helps us find the cause faster.
Frequently asked questions
Why do I get error 0x800CCC79 when sending?
Your outgoing server needs authentication. Tick My outgoing server (SMTP) requires authentication in your account settings.
Do these steps apply to Outlook Express?
Outlook Express is no longer supported by Microsoft. These steps apply to Outlook 2016 and later.
