If you're prompted to verify your account when you try to send an email message from Outlook.com, it is because we are trying to protect your account. Outlook.com will occasionally prompt you to verify your account, just to make sure you're still you and your account hasn't been compromised by spammers.
How do I verify my Outlook.com account?
Sign in to verifiy your Outlook.com account.
When you click the verification link, you're asked to type a series of random characters as shown in a picture. You can listen to an audio file that states the characters if you prefer. By entering the characters as shown, you prove that you're a human and not an automated program.
To make your account more secure, visit https://account.microsoft.com/security.