Microsoft Entra Workaround Helps Solve Outlook Encrypted Email Bug

Microsoft has acknowledged a growing issue affecting users of the classic Outlook email client when trying to open encrypted emails sent from other organizations. The problem, which is linked to Outlook Message Encryption (OMEv2), prevents many business users from accessing critical messages and is currently under investigation by the company.

According to Microsoft’s official support document, this problem impacts all Office channels where the classic version of Outlook for Windows is in use. When affected users attempt to open an encrypted email that originated from another tenant (or organization), Outlook displays the error message:

“Configuring your computer for Information Rights Management.”

This bug is particularly disruptive for enterprises that regularly exchange encrypted information across organizational boundaries. While Microsoft has not yet confirmed the root cause, it has issued a temporary workaround that administrators can apply to restore access.

Microsoft suggests two possible solutions, with one being more straightforward than the other:

1. Exclude external users from Conditional Access requirements.

2. Enable cross-tenant access to trust multi-factor authentication (MFA) claims from other organizations.

The second option—enabling cross-tenant MFA trust—is the recommended and easier solution. It allows encrypted emails sent between different organizations to be opened without errors, ensuring smoother communication across tenants.

Administrators can apply this fix by updating settings in the Microsoft Entra admin center. The steps are as follows:

1. Open the “Inbound access settings – Default settings” page in the Microsoft Entra admin center.

2. Select the “Trust settings” option.

3. Choose “Trust multifactor authentication from Microsoft Entra tenants.”

Once enabled, encrypted emails sent from your tenant to external users will open correctly. However, there’s a limitation: to access encrypted emails sent to you from other tenants, the sending organization must also implement this configuration on their side.

This means that both sender and receiver organizations need to coordinate and apply the same settings for seamless access to OMEv2 encrypted emails.

For more detailed steps, Microsoft has provided a support document on Entra configuration for encrypted content.

While the workaround restores partial functionality, Microsoft’s Outlook and Purview engineering teams are actively investigating the issue to deliver a permanent fix. The company has assured customers that it will provide updates once the root cause is identified and a patch is ready.

This is not the first time Microsoft has faced Outlook-related issues in 2024. In June, the company released a fix for a bug that caused the classic Outlook client to crash when composing new messages or opening existing emails. Later, in August, Microsoft mitigated another issue in Exchange Online that disrupted email access for Outlook mobile users relying on Hybrid Modern Authentication (HMA).