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In the Outlook web client, at the top of the client window, compose a new message.
In the new window that appears, at the top of the window, select Options
Click the small, downward-facing arrow under Encrypt
Select Connect to Rights Management Servers and get templates
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In your message pane, click Options at the top of the window.
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2. After clicking
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Options, in the top bar, click the small, downward-facing arrow under Encryptunder Encrypt
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3. Select
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Encrypt-Only from the drop-down menu that appears after you select the correct mailbox
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From the Encrypt drop-down menu, you can also select the following options:
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