For testing purpose, I created a new user profile and the trackpad is working as usual !. However, It is still not working on my main user profile. I did the following with no success so far:
- Re-install the macOS from the macOS recovery
- Delete the com.apple.AppleMultitouchTrackpad plist file from the ~/Library/Preferences through two ways: file system and Default command
- Reset the SMC
- Reset the NVRAM
macOS Catalina 10.15.5
Best Answer
Removing a preference list is not so good on macOS. First step is to let the database that tracks preferences to clear those entries.
Since the system may not read those settings, shut down after the above. Good news is you know the hardware and OS are fine. Worst case no one can help figure out how your account is corrupt and you back up your files and restore them to the new account with the working settings.