Open Project Properties window.
Select PICkit 3 under Categories.
Select Program Options from the Options Categories combo box
Check box if you want to enable low voltage programming (LVP).
For the LVP configuration bit set to "Low-voltage programming enabled", you may program in either high-voltage (default) or low-voltage (enabled here.)
For the LVP configuration bit set to "High-voltage on MCLR/Vpp must be used for programming", you may only program in high-voltage.
Not available on all devices.
This option is for programming only. It is not valid for debug operations.