Why My Outlook is Not Sending Emails

Email isn't supposed to be rocket science; you type a message, click send, and the message should be sent more or less instantly and arrive in the recipient's inbox at almost the speed of light. And usually, it works like this.

But every Outlook user has probably suffered from the mysterious and frustrating experience that Outlook inexplicably fails to send emails. Messages sit unsent in your outbox as you become increasingly agitated because you can't communicate with the outside world. This problem is more common than you might think, Outlook is Not Sending Emails, so here are five ways to fix and resolve a clogged Outlook outbox.

Resend the message

There are a lot of reasons why your email might not be sending, but the easiest potential solution is to try resending it. A momentary glitch or sync problem could have consigned the email to the outbox for longer than usual.

To resolve it, click the outbox in your folder list and double-click the email that won't leave. Click Send a second time and wait a few moments to see if that works. If not, you might try deleting the message and rewriting it from scratch. If you send this second message and it still won't budge, then move on to the next troubleshooting step.

Make sure Outlook isn't offline

Outlook could have been accidentally set to offline mode. This can happen if there's a temporary problem with your internet connection, for example, and Outlook fails to go online again after connectivity is restored. Check the status at the bottom right of the Outlook window — you should see Connected. If it says Offline, click the Send/Receive tab in Outlook's ribbon menu and then click Work Offline. This should de-select the mode and you should see the status revert to Connected.

Ensure you're connected to the internet

If the status remains offline, you might have an internet connection issue. See if you can go to a web page in a browser on the same computer. If you can't access the internet at all, reboot your WiFi network (unplug the internet modem and WiFi router, leave them powered off for at least two minutes, and then plug them back in again). Check your status after the network fully resets.

Close and restart Outlook

If you have a reliable internet connection but the email still won't leave your inbox, close and restart Outlook. You can't simply close the Outlook window, because Outlook leaves services running in the background. To make sure Outlook is fully closed, use the Task Manager.

1. Click Start and then type "task manager."

2. Click Task Manager in the search results when you see it appear.

3. Click Microsoft Outlook and then click End task.

4. Start Outlook again.

Repair Outlook or your profile

Microsoft offers some tools that can repair Outlook if certain aspects of the program get corrupted. If you still can't send email, it might be time to try to repair Outlook. This is a time consuming process (it can take up to an hour) so save this for a last resort.

Click Start and then choose Settings. In the Settings app's search box, type "apps" and then choose Add or Remove programs when it appears in the search results. Scroll down the app list and find Microsoft Office (depending on your version of Office, it might be labeled differently, like Microsoft 365). Click the three-dot menu to the right and choose Modify. Choose Online Repair and then click Repair.

If this doesn't fix the problem, you can also try to repair your email account profile. In Outlook, choose File, then Account Settings and then choose Account Settings again from the drop-down menu. In the Accounts Settings dialog box, click the email account that won't send mail and click Repair.

If you do not receive an error message while you try to send the email

The problem is likely to be related to your local Outlook configuration.

If Outlook is not sending only some Outbox emails, make sure you don’t have the habit to preview / open / click on Outbox emails: your Outbox emails should be unread (marked with bold & italic) otherwise Outlook will not send the email and it will be stuck in your Outbox folder. Check your Outbox emails:

— if the email is bold and italic, then it is ready to be sent;

— if the email is just marked with bold, then it was read;

— if the email is not marked with bold or italic, then the email was read and edited. As in the following screenshot, only the first email (with the subject “Unread email”) is going to be sent by Outlook while the other emails will stay in the Outbox folder: