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 It issues digital certificates, signs certificates to verify their validity and tracks which certificates have been revoked or have expired.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

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 ...

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

需要文档签名时，无需向人员发送多个草稿或来回电子邮件。 现在，可以在电子签名请求中附加文档，并直接在桌面或移动设备上的“审批”中发送文档。

To create an e-sign request, you’ll need to sign into your account with an available e-signature provider such as Adobe Sign or DocuSign. If you don't have account, it's easy to start a free trial or create an account. Choose the e-signature provider you'll use to create, send, and manage e-sign requests.

在Outlook 中，可以为电子邮件创建一个或多个个性化签名。 签名可以包括文本、链接、图片和图像 (，例如手写签名或徽标) 。

If you get an email from Microsoft account team and the email address domain is @accountprotection.microsoft.com, it is safe to trust the message and open it. Microsoft uses this domain to send email notifications about your Microsoft account. These notifications can include security codes for two-step verification and account update information, such as password changes. You can check the ...

Important: With two-step verification, you always need two forms of identification. This means that if you lose your phone, your password alone won't get you back into your account. For that reason, we strongly recommend you have three different sign-in methods associated with your account.

Learn how to manage your Microsoft account security info and troubleshoot verification code issues.

The Office @mention feature makes it much easier for you to connect with colleagues and needed resources as you collaborate on creating documents, presentations and spreadsheets.