When you sign in to Skype with your Microsoft account, you might be asked to provide an alternative email address or phone number. This is just to make sure that your account is always protected. We’ll ask you to verify your details about every 6 months just to keep your account secure.
If a pop-up window appears and asks you for this security info, please provide an email address or phone number. We’ll send you a security code, which you enter in the window, and then you’re signed in to your account.
If you don’t verify your Microsoft account with the security code within 7 days, your account will be locked out. If that happens, simply repeat the verification process.
Find out more about adding security information to your Microsoft account.