Microsoft is investigating a known issue that triggers Outlook errors when opening encrypted emails sent from other organizations.
According to a recently published support document, this issue affects users in all Office channels who are using the classic Outlook email client.
“Currently, when using classic Outlook for Windows, you can’t open an OMEv2 encrypted email if it was sent from a separate organization (what we call another tenant),” Microsoft said.
“If you attempt to open the encrypted email, you may see the following error message: ‘Configuring your computer for Information Rights Management’.”
While the cause of the issue is still being researched, Redmond has shared a temporary workaround for impacted customers, which requires them to either exclude external users from Conditional Access requirements or enable cross-tenant access to trust MFA claims from other organizations.
As the company explained, enabling cross-tenant access is the easiest solution, as it allows encrypted emails sent to other external tenants to be opened without an error.
To do that, you will have to go through the following steps:
- Go to the “Inbound access settings – Default settings” page of the Microsoft Entra admin center. Then select “Trust settings” via this direct link.
- Select the option for “Trust multifactor authentication from Microsoft Entra tenants.”
It’s important to note that applying this workaround will only ensure that others can open encrypted emails sent from your tenant. To open encrypted emails sent to you from another tenant, the sending organization must also perform the same workaround on their system.
You can find more information regarding Microsoft Entra configuration for encrypted content in this support document.
Microsoft says the Outlook and Purview teams are investigating the bug and will provide more information as soon as possible.
In June, Redmond fixed another bug causing the classic Outlook email client to crash when starting a new message or opening emails.
Two months later, it mitigated an Exchange Online issue causing email access problems on Outlook mobile for customers using Hybrid Modern Authentication (HMA).
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