The Cortana gets SMS messages from your smartphone in Windows 10 anniversary update and allows users to reply to those messages with Cortana. The new feature is working well on my computer clean install, but I could not get the messages and the action center never show the app notifications from the desktop after upgraded my Surface Pro 4 tablet. I access the Settings app and notice that Show app notifications option is greyed out in Notification and actions pane, so it causes the problem.
How to fix “Show app notifications” option greyed out in Windows 10 settings app after anniversary update
* Press WIn + R from your keyboard, type regedit into Run dialog box, and hit Enter to open Registry Editor. Or you can click on Start button, type regedit to search and select it from results.
* Navigate to the location below:
and go to its right side pane, double click on the ToastEnabled string, change its value data to 1 in the pop-up box, and click OK button to save that.
* Then return to left pane and go to another tree:
Select PushNotifications key and go to its right pane. Repeat the same way to modify the Value data of ToastEnabled to 1.
* Close the Windows Registry Editor and re-open the Setting app to check if the WIndows 10 can toast the app notifications to action center on your desktop.
For Windows 10 Pro or Enterprise users, you can do that by local Group Policy Editor.
* Press Win + R keys, input gpedit.msc and hit Enter.
* Go to the folder below:
User Configuration > Administrative Templates > Start Menu and Taskbar > Notifications.
* Then double click on “Turn off toast notifications”, check Disable box, and click OK.