Save your work, and close any open programs to protect against accidental data loss. Shut down the MacBook Pro.
Unplug the MagSafe power adapter if your MacBook has a removable battery. Alternatively, plug in the MagSafe power adapter if you cannot take out the battery.
If you have taken out the battery, press and hold the power button for at least 5 seconds. Release the button. If you plugged in the MagSafe power adapter, press the keyboard keys Shift, Ctrl, Option and the power button at the same time. Release all keys simultaneously.
Insert your battery if you took it out, and plug in the MagSafe power adapter. Turn on the MacBook Pro to complete the process. If you already had the MagSafe power adapter connected, press the power button to turn on the MacBook Pro. Test for similar problems you had before resetting the SMC, and use your computer normally.