We’ll let the experts explain this one.
Visit Microsoft's Encrypt email messages page for more information.
Email encryption types
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specific to Cal Poly Office365
Cal Poly Office365 Outlook offers four types of encryption permission. To change the permission for a message, create a New Message. Click on Encrypt and then click on , click Encrypt, then click Change permissions. Select the appropriate encryption type from the dropdown list.
The four types of encryptions encryption are:
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| title | Encrypt-Only (or simply "Encrypt" in Outlook web) |
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 - Messages that have the encrypt-only policy applied can be read directly in Outlook on the web, in Outlook for iOS and Android, and Outlook for PC versions 2019 and Office 365.
- When Encrypt is first selected as an option while drafting an email, this is the default setting providing standard O365 encryption for email transporting within Cal Poly (@calpoly.edu). Recipients external to Cal Poly will receive a message with a link provided. That link will take Office 365 users to Outlook on the web to read their message. Users with other email accounts (e.g. gmail) will be prompted to go through a process to obtain a one-time passcode and to read the message in a browser window.
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Only the recipients of the email will be able to view and reply. They cannot forward or , share with other people or print. Even if someone the sender did not specifically give permission to access the file gets it, he or she will not be able to view the contents, because the policy is checked upon opening and the information is encrypted the entire time. |
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 - Only users that belong to Cal Poly's implementation of Office 365 (that is, people with an Office 365 account that ends with @calpoly.edu) can access the content, make edits, and share with others inside our implementation of Office 365Cal Poly. Recipients/addresses without a calpoly.edu account that receive messages with this setting will get notification of not having permissions to read the message if attempted.
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| title | Confidential View Only |
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 - Only users that belong to Cal Poly's implementation of Office 365 can view this content but cannot edit or change it in any way. They can print and share with others inside our Cal Poly's implementation of Office 365. Users external/without calpoly.edu addresses receiving messages with this setting will get notification of not having permissions.
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