Want to add a padlock to your email messages? You can use encryption and digital signatures in new Outlook, classic Outlook, and Outlook on the web for work or school accounts to increase the security of messages. Encrypting an email message in Outlook means it's converted from readable plain text into scrambled cipher text. Only the recipient who has the private key that matches the public ...

Learn how to use mobile operator billing as a payment option to buy Xbox subscriptions, games, and other content.

Certificate authority (CA) A certificate authority is an entity similar to a notary public. It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired. Top of Page Digital signature assurances The following terms and definitions show what assurances are provided by digital signatures. Authenticity The signer is ...

See how to view the details for signatures and certificates.

Phishing (pronounced: fishing) is an attack that attempts to steal your money, or your identity, by getting you to reveal personal information -- such as credit card numbers, bank information, or passwords -- on websites that pretend to be legitimate. Cybercriminals typically pretend to be reputable companies, friends, or acquaintances in a fake message, which contains a link to a phishing ...

The Microsoft Authenticator app helps you sign into your accounts when you're using two-step verification.

Here are the most likely causes for an unrecognized charge: A Microsoft subscription has recurring billing enabled. Someone you know, such as a family member, bought something with your card. You can now investigate this on the Manage your payments page. A previously declined charge was charged again. A pre-order or split order was shipped. Someone made an in-app purchase from an app, game, or ...

Use the Information Protection viewer to view protected files in Windows, Android, iOS, or Edge.

About digital signatures and certificates in Office, and buying a digital certificate from a certificate authority or create your own.

Learn how to create and save a passkey to sign in to your Microsoft personal or work/school account and many other websites, apps and services.