Hi Debbie,
For your concern, I have tried reproducing the issue with the To Do Task list in my New Outlook desktop app but on my test environment, it still opens the email link normally from To Do side bane inside Outlook and inside the Microsoft To Do app.


Therefore, for the best possible assistance, could you provide more detailed information about this situation? I appreciate your understanding and cooperation.
- Are you using New Outlook, classic Outlook or Outlook on the web when the issue happens?
- Are you using Windows or MacOS device?
- When you click "open", what exactly happens (nothing happens, it opens Outlook but not the email, it shows an error, etc.)?
- Can you share a screenshot of the task where "open" does not work and also the sidebar workaround where the envelope works?
Please understand that my initial response may not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.
Thank you for your understanding. I look forward to hearing from you.
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