USB Keyboard Not Working At Login Screen

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Level 1

53 points

USB Keyboard Not Working At Login Screen

After waking my brand new Mac Pro (OS X 10.7.4) from sleep, my usb keyboard sometimes becomes unresponsive. So, at the login, I am unable to type my password in order to restore my session.

Is there a reason for usb devices to not work after waking the mac up? I tried all of the usb ports on the mac, as well as all the ports on both monitors. Thankfully, I have a bluetooth mouse and that works. But no idea why the usb devices stop working all together...

My software is completely up to date. And since this computer is less than a month out of the box, I'm puzzled as to why there would be any issues with it. Please let me know if there is a setting that affects this and what I need to do to fix it.

Thanks!

Mac Pro, Mac OS X (10.7.4)

Posted on Jul 24, 2012 7:22 AM

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Answer 1

Best reply

RatVega™

Level 4

2,005 points

Jul 24, 2012 5:24 PM in response to curtraymond

Make sure that the keyboard is plugged directly into one of the USB ports of the Mac Pro without daisey chainning. I had a similar problem when I attached my keyboard via a hub.

It's a pain, but you can also just unplug/replug the keyboard as a work-around. It's like the USB controller misses the KB until it's re-plugged (that is NOT a technical analysis... LOL)

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Answer 2

curtraymond Author

Level 1

53 points

Jul 25, 2012 6:48 AM in response to RatVega™

Maybe it needs to be plugged into the Mac before it goes to sleep...

Because when it wasn't letting me type anything I tried every USB port on the Mac itself, as well as the monitors, and even using an extender. Nothing worked.

However, I did eventually leave the keyboard plugged into the Mac and it woke up without a problem this morning. So, I'm hoping your solution did the trick!

Thanks

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Answer 3

MKulpa

Level 1

4 points

Oct 27, 2013 7:24 PM in response to curtraymond

You are not alone. I can use the keyboard to wake my Mac Mini but I can no longer use the arrow keys to select the user. If I select the user with my mouse the keys work again.

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Answer 4

Oct 27, 2013 7:29 PM in response to MKulpa

The keyboard and an Apple low-power mouse are very near the USB power limit. So don't plug anything but a low power mouse in the keybaord ports.

I plugged a self-powered printer into the USB at the other side of the keyboard, and the numeric keypad malfunctioned, but everything else seemed to work OK.

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