Troubleshooting: Outlook Error 0x80042109 on Windows PC

Microsoft Outlook error code 0x80042109 is a problem that occurs when sending messages through Outlook. Outgoing emails cannot reach the recipient, and a message appears on the screen informing you that there is a problem with the mail server. The problem seems significant and related to some kind of change, but in most cases, the user has not done anything about it.

While some Windows errors are related to system slowdowns, crashes, freezes, and similar problems, others appear as if from nowhere. System errors usually show up as BSOD windows or pop-up notifications, and software errors appear when you try to use a certain application, such as Microsoft Outlook.

What causes error 0x80042109 in Outlook?

Error code 0x80042109 usually occurs when users try to send emails through Microsoft Outlook. Their outgoing emails don’t reach their destination, and they see an error message on the screen telling them that there is a problem with the mail server. This problem doesn’t seem to affect other system processes. It does not cause the system to freeze, slow down or crash. It goes without saying that it only affects Outlook.

If you get the first error message, it means that you are having problems connecting to the Internet and cannot send emails successfully. The second message indicates that Outlook has stopped responding and you can no longer perform any actions. You cannot configure or update the program, which also prevents you from sending or receiving emails.

This problem may sound familiar to those who ask: “What is error 0x800ccc0e in Outlook?”. After all, the symptoms are very similar. Whether you encounter error 0x80042109 or error 0x800ccc0e, we are confident that our solutions will help you send and receive emails successfully.

How to solve the Outlook error 0x80042109?

Connectivity Check

For obvious reasons, your email client can’t connect with the servers, and as a result, you can’t receive or send emails.

If your connection is bad and you are sure that this is the reason for the Outlook error, you should perform the following steps to check the connection:

  • Restart your router and modem.
  • Switch to a wired connection instead of a wireless one.
  • Reboot your computer.
  • Temporarily disable the proxy server and VPN.
  • Run the Windows troubleshooter.

Once you have a stable connection again, the problem should be resolved.

Reconfigure the firewall

The Windows firewall doesn’t often block trusted Windows features, but obviously, it can happen from time to time. To check if the firewall actually allows Outlook access to the Internet, do the following.

  1. In the Windows search bar, type Firewall and open Windows Firewall.
  2. In the left pane, click on “Allow an application or feature through Windows Firewall”.
  3. Click on the “Change settings” button.
  4. Now find these 2 processes and enable them for private and public networks:
    Outlook.exe (for Outlook)
    Msimn.exe (for Outlook Express).
  5. Then confirm the changes and restart your computer.

Changing the Outbound Port

It seems that many ISPs are blocking this port value so you cannot send mail.

You have two options in this scenario:

  1. Change the SMTP value to 26.
  2. Switch to the TLS port and select 587.

The second option is a non-standard port value, but this is a proven solution to this problem. Follow these instructions and everything will be fine:

  1. Open Outlook.
  2. Select Tools.
  3. Open the account settings.
  4. Double-click the faulty email address.
  5. Select Advanced settings.
  6. Open Advanced.
  7. Set the outgoing SMTP server port to 587 and select TLS encryption.
  8. Confirm the selection and verify the changes.

Frequently Asked Questions

  1. Start Outlook, then click Tools.
  2. Go to Account Settings, then double-click the email address.
  3. Select Advanced Settings, then click Advanced.
  4. Change the SMTP port on the outgoing server to 587, then select TLS encryption.
  5. Confirm your changes.

  1. Make sure you have an Internet connection.
  2. Check your Outlook email account settings.
  3. Delete the suspicious message from your mailbox.
  4. Check your firewall settings and disable email scanning with an anti-virus program.
  5. Restore Outlook or Outlook Express.

If you get Outlook error 0x80042109, your recipient cannot receive your email. An error message that appears when you send an email through Outlook indicates a problem with your mail server. It could be due to Internet connection problems or Outlook not responding.

  1. Use keyboard shortcuts to delete.
  2. Delete deleted items.
  3. Edit emails marked for deletion.
  4. Mark items for deletion in the settings.
  5. Use the inbox recovery tool.
  6. Restart Outlook in safe mode.