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I have a MacBook Air model A1466. The keyboard seems to have been disabled. When I used an external key board, the system performs well. Please guide me how to enable keyboard in this model. Thanks.
See if you can boot in Safe Mode by holding down the Shift key on start up, This will eliminate it being a settings issues. UPDATE Here’s how to replace the keyboard: https://www.youtube.com/watch?v=2PyhbiwU… Before doing that check your trackpad cable, see step #6 of this guide: MacBook Air 13" Mid 2013 Trackpad Replacement
More info is needed; did your keyboard work previously, before you started using the external one? If so, check your keyboard input sources. Your computer may be looking for the external device instead of using the built in one. My computer is from 2009 so your menus may be different, but I’d start by looking at system preferences -> keyboard to see whether you can choose to stop using the external one. (If it is a bluetooth keyboard, you my also try turning off bluetooth at the top of your screen.)
