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This is moved here from the support system for informational purposes:

Question:

Cloud Drive and Cloud Sync apps are listed multiple times in "Notifications and actions" system settings in Windows 10.

The list has become quite big already. If you have any suggestion on how to resolve the issue, please let me know.

Answer:

It is an unresolved bug in Windows 10. Basically even uninstalled apps remains there:

http://answers.microsoft.com/en-us/windows/forum/windows_10-start/in-settings-under-notifications-and-actions-show/651f8f68-cf7b-4d19-ba61-56d027248be9
http://answers.microsoft.com/en-us/windows/forum/windows_10-other_settings/remove-an-uninstalled-app-from-the-notification/6cb57f86-23fd-4261-8922-e49f344095e5

http://answers.microsoft.com/en-us/windows/forum/windows_10-start/uninstalled-programs-still-appearing-in-show/f8f94dcc-9dd0-49d5-876f-44043cb038f6
http://answers.microsoft.com/en-us/windows/forum/windows_10-start/settings-shows-notification-option-for-uninstalled/2218ef52-a76d-4048-a6df-411ee4e79288

This post has a possible working/temporary solution until Microsoft fixes that:

http://answers.microsoft.com/en-us/windows/forum/windows_10-start/uninstalled-app-still-showing-in-notification/7bab3a62-5436-4d34-9b73-be2e0c77bc6b
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