To secure email in Outlook, users can apply several methods depending on their account type and subscription. Key methods include encrypting emails to prevent unauthorized access, sending messages with a digital signature to verify sender identity, and using Information Rights Management (IRM) to protect email content and attachments from actions like forwarding or printing. These features are mostly available to Microsoft 365 users, especially those with work or school accounts, and require setup such as obtaining certificates for digital signatures or enabling encryption settings in Outlook. Encryption options include S/MIME and Microsoft Purview Message Encryption, which can be applied to individual or all outgoing emails for enhanced security. Additional options include sensitivity labels and secure email add-ins for further protection and compliance. Here are the primary steps to secure emails in Outlook:
- Use encryption to convert email content to unreadable cipher text, readable only by intended recipients. Outlook supports S/MIME and Microsoft Purview encryption.
- Send emails with a digital signature (S/MIME) to authenticate the sender and ensure message integrity, requiring a digital certificate.
- Apply sensitivity labels and IRM to restrict actions like forwarding or printing of emails.
- For encrypted emails, recipients may need to authenticate via one-time passcodes if they are outside the organization's system.
- In Outlook desktop, users can encrypt emails by selecting the Options tab, choosing Encrypt or Do Not Forward, then sending the email.
- Outlook Web App also supports encryption by selecting the Encrypt option during email composition.
These security measures help prevent unauthorized viewing, tampering, and ensure compliance with organizational policies on sensitive information handling in emails.
