Filter Keys is an accessibility feature that instructs the keyboard to ignore brief or repeated keystrokes in order to make typing easier for users with hand tremors.
To activate Filter Keys – Press and hold the Right Shift key for 8 seconds. A tone sounds and the Filter Keys dialog appears. By default, the cursor is on the Yes button. Press the space bar to turn on Filter Keys.
To turn off Filter Keys, press and hold the Right Shift key for 8 seconds.