There is no fix available, but you can always revert to an older version.

Microsoft is looking into a newly identified issue in classic Outlook that prevents users from opening certain encrypted ...

You may see this error because the Microsoft 365 encryption service cannot verify your identity or check if you have permission to view the message. This is not ...

Microsoft has confirmed a known issue that prevents recipients from opening encrypted emails in classic Outlook.

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 ...