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 It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired.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.

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

A phishing email is an email that appears legitimate but is actually an attempt to get your personal information or steal your money. Some deceptive emails appear to be from a safe sender but, in fact, have a "spoofed" source address to fool you. Here are some ways to deal with phishing and spoofing scams in Outlook.com. Spoof intelligence in Exchange Online Protection helps prevent phishing ...

Signing your email messages with a digital ID helps to prove your identity and prevent message tampering.

How to create or edit your Outlook signature for email messages. Include your signature, text, images, electronic business card, and logo.

Whether it’s a new job title (congratulations!) or a phone number change, make sure you keep your email message signature up-to-date. If you're using new Outlook, for more information about email signatures, or if you haven’t created one yet, see Add a signature to messages. Select File > Options > Mail > Signatures. Select the signature you want to edit, and then make your changes in the ...

These steps are the same whether you're adding your first iCloud email account or additional iCloud accounts to Outlook. Select a tab option below for the version of Outlook you're using. What version of Outlook do I have?

If you can't remember your account name, use these steps to try to get back into your Microsoft account.

Outlook on the web is the web-based version of Outlook used by organizations and it's what you use to access the email, calendar, and contacts associated with your work or school account via a web browser. Your work or school account is typically assigned to you by someone in your organization.