@shaileng, Welcome to HP Support Community!
To isolate the issue, I would like to know the following:
How did you reinstall the Windows, retail copy or the OEM version?
Have you tried using an external mouse?
Try uninstalling the Touchpad drivers:
Press Windows+X to open the menu, and choose Device Manager on it.
2. In the device manager, expand category "Mice and other pointing devices".
3. Under this category, right click on your Synaptics Touchpad driver and click on Uninstall.
4. You may be required to confirm the uninstallation. Check the box next to "Delete the driver software for this device" and click OK button.
5. Restart your PC for the change to take effect. After restarting. Windows will attempt to reinstall the driver.
6. Do not perform any manual upgrades to the driver until it does automatically
Refer to this document to know how to use the touchpad.
Keep me posted for further assistance.
Cheers 🙂
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!
TEJ1602
I am an HP Employee