Outlook.com won't let me send an email

If you're having trouble sending messages in Outlook.com, try these solutions.

You can’t send email from a mobile device or Outlook app

ACTION REQUIRED: Reconnect Outlook desktop and mobile apps to Outlook.com for uninterrupted email access.

Earlier this year we introduced the new Outlook.com, which helps you focus on what matters, collaborate effortlessly, and get more done. As part of the upgrade, we are also moving accounts to a more secure and reliable infrastructure. You’ll need to reconnect your Outlook desktop or mobile apps to your Outlook.com account to ensure the best experience and fix issues. For detailed instructions and help on how to reconnect your account, please see this article.

If you have already reconnected Outlook, but are still unable to send or receive email, your account might be temporarily blocked because we noticed some unusual sign-in activity. To learn how to unblock your account, see Unblock my Outlook.com account.

You recently changed your password

If you changed your password for Outlook.com, you may need to change your email account settings in Outlook and in your mobile apps too.

The message or attachments are too large

If you've connected your Outlook.com account to the Outlook desktop or mobile apps and you try to send a message with an attachment that's larger than 25MB, Outlook won't send the message.

To fix the issue, go to your Outbox and then open the stuck email messages. Start with the oldest message first. If the message has an attachment that’s larger than 25MB, delete the attachment and either attach a smaller file or attach a link to the attachment. You can then try to send the message again. To learn more about attaching files to messages, see Attach files to email messages and calendar events in Outlook.com or Outlook on the web.

Check the “To” address line

Make sure that the email addresses of the people you are trying to send to are formatted correctly. If you try to send a message to an incorrectly typed email address, an error message will appear.

A screenshot of an address formatting error in Outlook.com.

You've exceeded the daily message limit

To help deter spammers, Outlook.com limits the number of messages that can be sent in one day. If you receive a message that you've reached the daily message limit, try the following: You can also Increase your message limits.

  • Save your email as a draft and send it the next day.

  • Increase your message limits by adding security info to your account.

  • If the email was created on a mobile device, tap to close the message. You'll receive a prompt asking you if you want to save or delete the message. Select Save and then Sync. You can then to go Outlook.com on a computer, open the draft, and send it.

You've added too many recipients to one email

Outlook.com limits the number of recipients you can add to an email message. If you exceed the limit, an error message will let you know how many recipients you can add to your email. Remove some recipients and then try sending again.

Your content triggered junk email filters

Outlook.com blocks the sending of messages when the content looks like junk email to the Outlook.com junk filters. Occasionally, legitimate email can be marked as junk. If your message is blocked, try changing the content of your message and then try sending it again.

Increase your message sending limits

You can increase your sending limits by adding security info to your account. Go to your Microsoft account security page, select Update info, and add the following security info to your account:

Phone number

  1. Select Add security info.

  2. In the dialog box, enter your phone number.

  3. Select Next and follow the on-screen instructions.

Alternate email address

  1. Select Add security info.

  2. In the dialog box, select the arrow next to A phone number, and select An alternate email address.

  3. Enter an alternate email address.

  4. Select Next and follow the on-screen instructions.

Two-step verification

  1. Select Set up two-step verification.

  2. Enter your password, and select Sign in.

  3. Select Next and follow the on-screen instructions.

Insufficient permission

Information Rights Management (IRM) allows senders to specify access permissions for their email messages, which might include preventing messages from being forwarded, read, printed, or copied by unauthorized people. To learn more about this feature, see Introduction to IRM for email messages.

See Also

Organize your Inbox with Archive, Sweep, and other tools in Outlook.com

Share Facebook Facebook Twitter Twitter Email Email

Was this information helpful?

Great! Any other feedback?

How can we improve it?

Thank you for your feedback!