Maybe filter keys or sticky keys are on?

Try this Solution…

  1. Click “Start” and select “All Programs.”¬†Click “Accessories” and select “Ease of Access.” in windows XP. Or Click “Start” and search “Ease of Access” in Windows 7,8,10.
  2. Click “Ease of Access Center.”
  3. Click “Make Keyboard Easier to Use.”
  4. Click “Set Up Sticky Keys.” Deselect the checkbox that says “Turn on Sticky Keys When Shift is Pressed Five Times.”
  5. Make sure the box that says “Turn on Sticky Keys” is not checked. Click “OK” to save your changes.
  6. Click “Set Up Filter Keys.” Uncheck the box that says “Turn on Filter Keys.” Uncheck the checkbox next to “Turn On Filter Keys When Right Shift Is Pressed For 8 Seconds”. Click “OK” to save your changes.
  7. Click “OK” again to save all of the keyboard accessibility changes you have made.

 

Hope this will help to solve your problem.