Email Encryption – Office 365 Email Encryption Recommendations

The theme of this month’s Tech Tips is all about the multiple encryption options offered by Microsoft Office 365 to help you meet your business needs for email security. As previously explained, there are three options of Email Encryption available in Office 365: Office Message Encryption (OME), IRM (Information Rights Management), and Secure/Multipurpose Internet Mail Extensions (S/MIME). But how do you know which encryption option is the right one for you? Below please find a quick summary of Microsoft’s recommendations, as well as example scenarios on when to use which type of Email Encryption.

Microsoft recommends using OME when you want to send sensitive business information to people outside your organization, whether they’re consumers or other businesses. For example: 

  • A bank employee sending credit card statements to customers 
  • A doctor’s office sending medical records to a patient 
  • An attorney sending confidential legal information to another attorney

Microsoft recommends using IRM when you want to apply usage restrictions as well as encryption. For example: 

  • A manager sending confidential details to her team about a new product applies the “Do Not Forward” option. 
  • An executive needs to share a bid proposal with another company, which includes an attachment from a partner who is using Office 365, and require both the email and the attachment to be protected. 

Microsoft recommends using S/MIME when either your organization or the recipient’s organization requires true peer-to-peer encryption. For example:

  • Government agencies communicating with other government agencies
  • A business communicating with a government agency

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