If you don’t have Project Plan 365 installed on your device, after clicking on “Open in Project Plan 365” button from the email you will be redirected to a page where you can first download the latest version of our app by clicking “Download Project Plan 365”. After installing the app, go back to browser and click on the “Open in Project Plan 365” button, click again the “Open Project Plan 365” button from the browser request dialog and the app will open. Lastly, Sign In with your email and password for the file to open.

Note: Check the “Always allow projectplan365.com to open links of this type in the associated app” so the browser request message won’t appear every time you open a .mpp from an email and it will open the file directly.