Macbook Air (2013) trackpad not responding
I tried SMC reset guided by the excellent Apple tech support.  But it did not solve the problem.  Just as PRAM zapping did not.

His suggestion of removing 2 plist items from the library did solve(!) the problem.


~/Library/preferences/com.apple.driver.AppleBluetoothMultitouch.trackpad.plist
~/Library/preferences/com.apple.AppleMultitouchTrackpad.plist


Apparently, one of these two got damaged; trashing them with a RESTART generates fresh plist files. Problem solved, thanks Apple!