USB Keyboard not working after Macbook wakes up from sleep I have a standard Windows PC-compatible USB keyboard plugged into my Mac. It works just fine, but whenever I wake my Mac up from sleep, I am forced to unplug and replug the keyboard from USB to get it to work.
I would reset both your PRAM/NVRAM and your SMC. See below for instructions.

Reset your PRAM/NVRAM

Older Macs had what's called Parameter RAM (PRAM), newer Macs use Non-Volatile Random-Access Memory (NVRAM). It may be worth you also resetting this. Here’s how to:


Shut down your machine. Yes, a full shut down, not just logging out.
Press the power button and then press the commandoptionpr keys. You have to make sure you press these keys before the gray screen appears or it won’t work.
Hold those keys down until your Mac reboots again and you here the startup chime.
Let go of the keys and let your Mac reboot normally.


Note: When you log back in you may need to readjust some of your system preferences (e.g. mouse speed, time and date/timezone, etc).

Reset the SMC

Your computer's System Management Controller (SMC) can also be reset. However, the instructions for doing this on MacBooks differ depending on the type of battery they use. Since your question has specified the model, I've provided both sets of instructions below:

For MacBook Pros, MacBook Airs, and MacBooks where you can’t remove the battery on your own (i.e. it's a built-in battery), here’s what you do:


Shut down your computer
Keep the MagSafe adapter (or power cable) plugged in.
Press at the same time shiftoptioncontrol (on the left side of the keyboard) and the power button
Let go
Turn your computer back on with the power button.


For MacBook Pros, MacBooks etc that you can remove the battery from, here’s what you do:


Shut down your computer
Disconnect the MagSafe plug (or power cable) from the computer
Remove the battery
Press the power button for 5 seconds and release
Put the battery back in
Reconnect the MagSafe cord (or power cable)
Turn your computer back on with the power button