Microsoft updated the Mail, Calendar and People App in the Windows Store on June 26. After that update, a number of people, including myself, found that the app would open but then “crash” immediately. It still would be running in the background, but would not display the default screen. I saw this on 4 Windows 8.1 computers. I checked the 2 computers running Windows 8.1 that had not yet been updated with the latest revision of the app and they worked fine. I upgraded to the new App release on one of these two computers, and as expected, the crashing behavior started.
After reading the initial complaints that started appearing in the Microsoft Forums http://answers.microsoft.com/en-us/windows/forum/windows8_1-winapps/windows-store-app-update-breaks-people-app/cd14abd2-1bc5-40d8-9e09-a51c66bfea2a I started digging into this. My hunch, reinforced by my logs and the log from another user, was that something in the social media integration function was causing the issue.
I found that link to control which social media accounts were linked to my Microsoft ID: https://profile.live.com/cid-27a6342ef735cc0f/Services/?view=manage
It turns out that the Twitter integration was causing the issue for me. After removing the Twitter integration, the App functions as it should and displays properly.
And yes, the Facebook Connect piece is now deprecated, but that was not causing the crashes.
I’m not 100% convinced that Microsoft has escalated the issue to the team that owns the app.