I cannot send mails through outlook

Question

The outlook program starts but when sending out mails is fastens (does not reply) and I have to start up again. But same thing happens over and over, i.e. it does not reply when sending out mails

Answer 1

Hi Frank Miltenburg,

Thank you for posting your question in the Microsoft Q&A forum. 

In addition to the troubleshooting steps Q&A Assist already suggested, I want to share one more data point that may fit your scenario. Your symptoms could be related to a known issue affecting POP accounts in Classic Outlook after installing the Windows 11 update KB5074109. Microsoft’s advisory is here: Classic Outlook POP account profiles hang and freeze after Windows 11 update to KB5074109

Numerous cases have been reported, and several users have confirmed that uninstalling KB5074109 allowed Outlook to work normally again.

If you find that KB5074109 is installed, you may want to consider uninstalling it and then restarting your computer. Here are the steps:

1. Open Settings > Windows Update
2. Choose Update history
3. Scroll down and select Uninstall updates
4. Locate KB5074109
5. Click Uninstall, then restart your computer

Note: Removing an update may reduce security posture temporarily, so if you’re in a managed environment, please coordinate with your IT administrator.

I hope this helps.

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Answer 2

If you are experiencing issues with Outlook freezing or not responding when trying to send emails, there are several potential causes and resolutions you can consider:

1. Check for Updates: Ensure that you have installed the latest updates for Outlook. Outdated software can lead to performance issues.
2. Antivirus Software: Sometimes, antivirus software can interfere with Outlook. Consider disabling any Outlook integration within your antivirus software or any antivirus add-ins installed in Outlook.
3. Corrupted User Profile: Your Outlook user profile may be corrupted. You can create a new user profile to see if that resolves the issue. To do this, go to Control Panel > Programs > User Accounts > Mail > Show Profiles, and then add a new profile.
4. Repair Outlook: You can try repairing your Microsoft 365 programs. This can fix issues caused by corrupted files.
5. Selective Startup: Performing a selective startup can help identify if other applications or services are causing conflicts with Outlook. You can do this through the System Configuration tool in Windows.
6. Check Mailbox Size: If your mailboxes are too large, it can cause performance issues. Consider archiving old emails or cleaning up your mailbox.
7. External Content: If Outlook is trying to load external content (like images in emails), this can also cause it to freeze. You may want to disable automatic downloading of external content.

If these steps do not resolve the issue, consider using the Classic Outlook Advanced Diagnostics troubleshooter to automatically check for problems.

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References:

• Outlook not responding error or Outlook freezes when you open a file or send mail
• Outlook not responding error or Outlook freezes when you open a file or send mail