Applies ToOutlook for Android Outlook for iOS

What are the requirements for running S/MIME?

  • Active subscription to Office 365, currently running the new Microsoft sync protocol

  • Current mailbox resides within O365 tenant (must be native EXO mailboxes)

  • Ability to update Exchange policy to permit pfx attachments over email

  • iOS: Running 11.0 and higher

  • Android: Running 4.4 and higher

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