Hello Sir/Madam. Thank you very much for giving us an opportunity to help you. I am Jins here to assist you. Please remember these things when we deal with your issue. It may take more than one step/answer to solve a problem. So If my answers don’t work or if you are not satisfied, please don’t Rate my answer as Bad or Poor Service, but please Reply back to me by clicking the “Continue Conversation” or “Reply” button and I will gladly continue to help. Remember, only Rate answer after you are 100% Satisfied. Please do not rate an answer, if you are not satisfied.
First of all, try to boot in to Safe mode. Reboot your Mac in safe mode by following the instructions on http://www.wikihow.com/Start-Your-Mac-in-Safe-Mode
If it is working on Safemode, just restart the system and boot normally. Check the result again.
Then you need to re-install mac osx. Your files and settings will not be touched as long as you don't specifically tell the installer to erase them. Follow below steps to re-install osx.1. Insert your Mac OS X Install DVD or Installation Disc 1.2. Restart the computer and hold down the letter "C" as the computer starts up.3. Continue to hold down the letter "C" until you see a grey screen with an Apple and a small spinning gear.4. Select your language on the Welcome to the Mac OS X Installer screen and click "Continue".5. Click "Continue" on the following screen.6. After reading the Software License Agreement, click "Agree".7. Select the volume to which you are going to install. "Macintosh HD" is the default name.8. Click the "Options" button in the bottom corner of the window and select your installation type.9. Click "OK" and then "Continue". You will be presented with a confirmation window at which point you can click "Install" to proceed.I hope re-install will fix the issue. Try and let me know the result.RegardsJins