Just recently, a friend brought his MacBook Air (MBA) to me complaining he can no longer login to his MBA. He thought it was some issue with the system. We tried but could not login. Luckily, his laptop had a user account without a password, so we got in, and based on my suspicion we opened a note application and typed. And lo! All the characters were in CAPS even when the CAPSLOCK is OFF.
After a brief research online the following resolved the problem.
PRAM = Parameter RAM. It stores stuffs related to settings. And sometimes strange values get written on it or gets corrupted.
Steps to reset PRAM on Mac:
• Shut down the computer.
• Locate the following keys on the keyboard: Command, Option, P, and R.
• Turn on the computer.
• Press and hold the Command+Option+P+R keys as soon as you turn on the computer - before the gray screen comes up.
• Hold the keys down until the computer reboots again and you hear the startup sound for the second time.
• Release the keys.
The issue with the keyboard only typing in CAPS is now resolved.