How to fix “550 5.3.4 Requested action not taken…” error

If you are setting up your email client to access your Hotmail or Outlook.com email account and are receiving the following error:

550 5.3.4 Requested action not taken; We noticed some unusual activity in your Hotmail account. To help protect you, we’ve temporarily blocked your account

Then follow these instructions to unblock your Hotmail or Outlook.com account:

1. Sign-in to your Hotmail or Outlook.com account
2. At the top-right corner, click your name , then click the Account settings menu item
3. Select Overview menu (left-pane), then click the Security info menu item
4. Under the Phone number heading, click the Add link
5. Select your country from the drop-down list, then enter your phone number
6. Select Text from the Verify phone via: option, then click the Next button
7. Check your mobile for a new SMS/text message from Microsoft (may take a few minutes)
8. Enter the code you received via SMS/text into the Code field, then click Next
9. Microsoft will now verify the code given and unblock your account
10. You should now be able to access your Hotmail or Outlook.com account via your device’s email app
11. If you are still receiving the error, contact Microsoft Support

• Contact Microsoft Support (official)
• Outlook.com Help and guides (official)
• Search Google for Outlook.com