Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've noticed that this started happening maybe a few weeks ago:

When I'm logging in, sometimes when I type an underscore in my password, it does not register as a keypress, i.e. no black dot appears in the password field. It only happens some of the time.

I noticed it because a few times when I was logging in, it said I typed the password incorrectly (because the underscore was missing). I then began to type the password slowly upon logging in after those few times, and I noticed that the underscore would fail to be recognized at times.

I'm quite sure I'm typing it properly, because now I will very slowly and deliberately type the password with the intent of watching this bug happen. Typically it will happen, and then I will type the underscore again and it will register.

This happens both on my MBP's keyboard and with a USB keyboard. It's pretty easy to replicate, as it will happen almost every time I have to unlock the screen from sleep.

Any ideas?

share|improve this question
Do you notice the underscore character dropping out when you are logged-in and typing text in apps? – IconDaemon Sep 6 '12 at 1:33
@IconDaemon no, the underscore is fine in every app once logged in. I only notice this during login. It happened again just this morning, I very deliberately typed my password, making sure to press the keys firmly and it absolutely failed to recognize my first try at the underscore. – jemminger Sep 6 '12 at 14:16
Is this the only character in your password that requires the use of the Shift Key? – Stu Wilson Sep 7 '12 at 8:24
@StuWilson Yes, only this character requires the shift key. – jemminger Sep 10 '12 at 16:20
Try the original password with underscore but use a different shift key to make the underscore. Also try changing the password to one not containing the underscore but containing another character that requires the use of the shift key. – Stu Wilson Sep 10 '12 at 16:40

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.