External recipient can't download attachment on OME encrypted email

Question

We are attempting to use OME to send encrypted emails to external recipients. However, we want the external recipients to be able to download any attachments on the emails, and the attachments shouldn't have any restrictions on them. We used the following command to achieve this.

Set-IRMConfiguration -DecryptAttachmentForEncryptOnly $true

I tested the functionality of this by sending and encrypted email to a personal GMail account of my own, and all seems to work correctly. I'm presented with the options to either Preview or Download the attachments when opening the email via the OME portal.

However, when testing this with a business external recipient, when they open the email through the OME portal, they only have the option to Preview the attachments. I'm sending the email to both my Gmail and this external recipient in exactly the same manner, but getting two different behaviors.

Does anyone have any idea why this particular individual would not be able to Download the attachments?

Answer 1

I recommend taking a look at updating your labels and policies. This could be a good time to start looking to migrate to Sensitivity Labels from the Security and Compliance Center. Check this blog - https://techcommunity.microsoft.com/t5/security-compliance-and-identity/announcing-timelines-for-sunsetting-label-management-in-the/ba-p/1226179

Also, you can check these links for more insight - https://learn.microsoft.com/en-us/answers/questions/95843/office-message-encryption-recipient-not-able-to-op.html
https://techcommunity.microsoft.com/t5/security-compliance-and-identity/admin-control-for-attachments-now-available-in-office-365/ba-p/204007