We’ve noticed comments from many of you asking why we want you to verify your Microsoft security information. We’d like to explain why verifying this information is important. To help protect your email account and your personal data, we ask everyone who has a Microsoft account to make sure that the security information associated with their account is correct and up to date. When your security information (like an alternate email address or phone number) is current, we can use it to verify your identity.
For example, if you forget your password or if someone else tries to take over your account, Microsoft uses your security details to help you get back into your account.
If you see a message asking you to update or verify your Microsoft account security information, you have seven days to do it. If you no longer have access to your security information, you will have to fill out a support request.