Encrypted email is not working

Question

Encrypted email is not working

Anonymous

Unbale to open encrypted email, when I send encrypted email to someone they also unbale to open.

Viorel 127.2K Reputation points

2026-01-05T19:50:29.1933333+00:00
Did you and recipient apply all the recommendations from the documentation?

https://support.microsoft.com/en-us/office/send-s-mime-or-microsoft-purview-encrypted-emails-in-outlook-373339cb-bf1a-4509-b296-802a39d801dc

https://support.microsoft.com/en-us/office/open-encrypted-and-protected-messages-1157a286-8ecc-4b1e-ac43-2a608fbf3098

2 answers

Your answer

Viorel 127.2K Reputation points

2026-01-05T19:50:29.1933333+00:00

Did you and recipient apply all the recommendations from the documentation?

https://support.microsoft.com/en-us/office/send-s-mime-or-microsoft-purview-encrypted-emails-in-outlook-373339cb-bf1a-4509-b296-802a39d801dc

https://support.microsoft.com/en-us/office/open-encrypted-and-protected-messages-1157a286-8ecc-4b1e-ac43-2a608fbf3098

Answer 1

Hi Dogra,

Thanks for reaching out. I understand how frustrating it is when encrypted emails won’t open for you or your recipients. I'm here to help!

First, try opening the encrypted email using Outlook on the web instead of the desktop app. Also, signing out and back in or clearing your browser cache can refresh your credentials and resolve token-related problems.

Second, check for conflicting add-ins in Outlook. Disabling third-party add-ins, especially security tools.

Last, if you’re in a Microsoft 365 environment, ensure that your license supports Purview Message Encryption and that IRM (Information Rights Management) is enabled.

I hope you find this information helpful. Please let me know if you have any further questions If the answer is helpful, please click "Accept Answer".

Regards,

Carlo

Answer 2

If you or the recipient are unable to open encrypted emails, it may be due to several reasons related to Microsoft Purview Message Encryption. Here are some common causes and solutions:

Causes:

Connection Issues: The recipient's Outlook desktop client must connect to the Microsoft Azure Information Protection (AIP) endpoint for your Exchange Online tenant. If it cannot connect, the message may not open correctly.
Conditional Access Policy: An external-facing conditional access (CA) policy in the sender's tenant may block access to the AIP endpoint.
Multi-Factor Authentication (MFA): An MFA policy may add an extra layer of security that blocks access to the endpoint.
Sensitivity Labels: If a sensitivity label was applied to encrypt the content, it may restrict access to internal recipients only.

Solutions:

Adjust Conditional Access Policies: If a CA policy is blocking access, consider excluding AIP from the list of blocked cloud apps.
Check Sensitivity Labels: Ensure that the sensitivity label applied does not have restrictions that prevent external access.
Use Alternative Access Methods: Recipients can try opening the encrypted message in Outlook on the web or on mobile apps like Outlook for Android or iOS, which handle decryption differently.
Guest User Access: If the CA policy allows guest users, consider adding the external recipient as a guest user.

It is advisable to work with your organization's IT or security team to implement the appropriate resolution based on your specific environment and security requirements.