On iOS, certificates are stored in the publisher keychain. On Android, they are stored in the system keychain.

For information about how to request a digital certificate from a certification authority, ... To allow your recipients to send encrypted messages to you, make sure that you've selected your signing and encryption certificates, and then select Include my certificates in signed messages.

Learn how to use digital signatures, digital IDs, and signature lines in Microsoft 365 files, such as Word, Excel, and PowerPoint.

Update all servers that run Active Directory Certificate Services and Windows domain controllers that service certificate-based authentication with the May 10, 2022 update (see Compatibility mode). The May 10, 2022 update will provide audit events that identify certificates that are not compatible with Full Enforcement mode.

Use the Block or Allow settings in Outlook Web App to help control unwanted and unsolicited email messages.

How to get a digital ID or digital certificate for Outlook to prove your identity and prevent message tampering. Sign your emails with a digital ID.

Resolves a vulnerability in Windows that could allow spoofing if an attacker who is logged on to a domain-joined system runs a specially crafted application that could establish a connection with other domain-joined systems as the impersonated user or system.

Resolves a reported vulnerability that could allow spoofing in implementations of DNS.

Learn how to change the settings that enable or disable macros in Excel, and more. Change the macro security settings to control which macros run when you open a workbook.

Note: This feature is disabled by default and must be enabled after installing the update.For more information see Digital certificates and encryption in Exchange Server.