Hi CCheukKa,
Thanks for your post in Microsoft Community.
It sounds like you are currently having a problem that unable to add keyboard.Sorry for the inconvenience.
This problem may be that the input method service is disabled by the software and cannot be started automatically,you can try the following solutions to see if they can solve your problem:
- Perform a clean boot to eliminate third-party software interference.
Please check here for details:How to perform a clean boot in Windows (microsoft.com)
Disclaimer: A “clean boot” starts Windows with a minimal set of drivers and startup programs. It helps to determine whether a background program is interfering with your game or program and to isolate the cause of a problem. These steps of "clean boot" might look complicated at first glance. However, to avoid any trouble for you, please follow them in order and step-by step so that it will help you get you back on track.
- Press Windows+R to open the Run > Type cmd in the box > OK > Enter command Ctfmon > Press Enter > Then restart the computer.
Feel free to post back if you need further assistance.
Best Regards,
Sawa | Microsoft Community Support Specialist
* Beware of scammers posting fake support numbers here.
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