Forum Discussion
Transport rule for encrypted messages
Modifying the content on an encrypted message is not supported, as detailed for example here: https://docs.microsoft.com/en-us/previous-versions/office/exchange-server-2010/bb124703(v=exchg.141)#message-types
Modifying the content on an encrypted message is not supported, as detailed for example here: https://docs.microsoft.com/en-us/previous-versions/office/exchange-server-2010/bb124703(v=exchg.141)#message-types
VasilMichevDoing some more digging into this, transport decryption is enabled by default in Exchange Online and set to "Optional" so transport rules can in fact read messages protected using AAD RMS. I've tested and this works fine (a disclaimer is added successfully to these messages). So my mistake was thinking that the "encrypted" message type also referred to these types of messages, when in fact it only refers to S/MIME protected messages.
I now need to find a condition I can use in a transport rule that can detect messages that have AAD RMS protection applied to it. We are using the "Encrypt" option in Outlook to do the protection which I understand uses the new OME, which uses AAD RMS (but I may be wrong)