I always disconnected my type cover and enabled the Tablet mode on my Surface Pro 4, so that I can easily read PDF and Office Word documents. However, after my tablet installed Windows 10 anniversary update, the screen rotate button had completely disappeared from the action center and the related options was missing in Display settings. Now I am stuck with no rotation charm and lost the ability to auto rotate.
How to fix Auto Rotation Lock Option missing/lost after Windows 10 anniversary update
The Hardware and Devices troubleshooter can help you updated the related HID sensors driver
* Open Control Panel > Hardware and Sound > Configure a device, check Apply repairs automatically box, click Next to scan for updated drivers, choose the ones you want to fix and click on Next to begin processing.
* After it is finished, make a rebooting and rotation come back.
* Or you can also search for a driver update in device manager manually.
Make change with key of regedit and that works for me
* Press Win + R from keyboard, type regedit into Run box, and hit Enter.
* Within the left pane of Registry Editor, go to the tree below:
* In its right pane, double click on the SensorPresent string, and change its value data from 0 to 1, and click OK button.
* Close regedit editor and reboot the system to check if it is working normally.
* If your device have connected with keyboard, just remove it.
* Open the Setting app, go to System > Display, click the drop down menu in “Orientation” section to choose the Portrait options, and click Keep changes option.
* Restart your tablet or computer. Then you should find the the Rotation Lock icon and get the auto-rotate function back.