Macbook Air keyboard trackpad NOT working AFTER login.
LAPTOP:
MacBook Air 13-inch, Early 2015
2.2 GHz, Intel Core i7
8 GB 1600 MHz DDR3
Intel Graphics 6000 1536 MB
HISTORY:
Prior to this problem, the laptop has worked perfectly. Both the built-in keyboard and trackpad worked flawlessly and simultaneously when Bluetooth keyboards and trackpads were paired with the laptop. I do not recall if any system or app update preceded the problem.
PROBLEM:
MacBook Air keyboard and mouse trackpad are ACTIVE and FUNCTIONAL at startup, BUT - do NOT work after that point. Both wired and wireless (Bluetooth) keyboards and trackpads/mice DO work.
TROUBLESHOOTING:
- Re-set System Preferences for anything with the words, "keyboard," or "trackpad," back to factory defaults;
- Other obvious LOW-level troubleshooting - same problem when moved to another physical location and WiFi network; problem persists when removing power source from Bluetooth hardware.
Because the keyboard and trackpad work at the initial startup, but do not function after logging into the system - I think this has to be a software problem...
Any help and insight will be appreciated.
MacBook Air, OS X El Capitan (10.11.6)