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Transforms the message from plain text in to unreadable ciphertext
Keeps the message in ciphertext while in transit to protect the message from being read if intercepted
Decrypts the message via a key or authenticated response
How to Encrypt an Email
How to Tell an Email is Encrypted
"Do Not Forward" Feature
Resources
Microsoft has provided the following resources/documentation for users to review regarding O365 encryption and message security:
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