I got my Gadget (Redmi Note 4) in February 2017 and am enjoying all its amazing features. However, there was one feature that was bugging me thats was "Calendar". Whenever I tried opening it, used to give me an error "Calendar" has encountered a Problem and need to close". This used to give me two options. Cancel and Report Bug.
After doing some R & D, these steps resolved the issue:
1. Go to Settings
2. Under the App settings click "Installed Apps"
3. The apps here are arranged in alphabetical order under the heading "All"
4. Find "Calendar" in the list and click on that
5. Click "Clear Data"
6. Come back on the main menu, restart the phone if required.
7. Access the Calendar now
Yippeeeee and its works really perfecto....
Let me know if this helps
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