I use MacBook Pro 15' with OS X 10.6.3. Today, I found that I cannot do left clicking after I switched user accounts from one to another. Whenever I click my mouse or one fingered click on trackpad, context menu for the area is poped up. Simply, I cannot click or double click anything. And same time, my keyboard is malfunctioning too. When I type anything, nothing is appeared in the monitor or some other letters those I did not typed are appeared. When I log in with other user account, I have no problem in the environment. But When I log out and log in again with a certain account, that is my main account, the same trouble is still exist. I did bellows : - Rebooted more than several times. - Reinstalled OS X. - Push and hold Cmd + alt + r + p while booting. (several times. But could not separated my battery because it is not allowed.) Nothing above could solve the problem yet. Any ideas or Advices?