Most slowness issues are simply related to your computer getting stuck in a particular area. These 3 resets resolve most slowness and startup issues:

  1. Restart your computer.
  2. Reset the PRAM. Shut down or turn off the computer. While holding command+option+R+P, press the power button. The computer will startup, and allow it to chime at least twice. After that, you can let go of the keys and let the computer start up normally. Click here for more information regarding this reset along with an instructional video. 
  3. Reset the SMC. If you are unable to perform the previous steps or they did not resolve your issue, resetting the power (SMC) may be necessary. Connect your power adapter. Press and hold the shift+control+option+power buttons for 5 seconds. The power adapter light will change from green to amber after a few seconds. Click here for more information regarding this reset along with an instructional video.