Just installed Windows 10 and noticed that I have no way to disable my touchpad on my Asus S550CA Computer.  There is supposed to be a feature where you press fn+F9 to disable it but that is not working any longer.  I have tried going into the new Settings feature and under the Mouse/Touchpad section there is no way to disable the touchpad.

Anyone else having this problem and more importantly does anyone know how to fix this?

I was having this problem and found no solutions online, so after some fiddling around, I was able to successfully disable my touchpad while keeping the mouse fully functional.

Basically, you must uninstall your current driver; then, upon a restart it will automatically install the updated driver with which you can disable with Fn+F9 normally.

These are the steps to do so:

• Open up the Control Panel, then search for “Mouse” in the upper right search bar. Click on the first result to open up a “Mouse Properties” box.
• Navigate to the rightmost “Hardware” tab to find installed touchpad devices. Assuming device drivers for a mouse are installed, click on the device which is not your mouse. For my system, it was named, “Asus Support Device.”
• Once you have selected it, click on the “Properties” button near the bottom right to open up the device’s properties.
• A new box will appear; go to the second tab named “Driver” on it. Continue by clicking on the “Uninstall” button on the bottom. A new dialogue box will appear. Ensure that you will not “delete driver software,” and click “OK.”
• It will then ask you to restart your computer. Do so. After the restart, it should tell you that it is installing the new device driving for “ASUS Touchpad.” In my situation, it required me to restart my computer again.
• After the second restart, your touchpad driver should be completely up to date, and Fn+F9 will disable the touchpad, as it should.