While holding down the C6 key (right-most key on the keyboard), turn the power switch on.
1. Press the [FUNCTION] button.
2. Press the [I] [UTILITY] button
3. Press the Tab button to select [SYSTEM RESET] in the display
4. Press the [D] button [FACTORY RESET EXECUTE]
*For more detail concerning specific parameters that can be factory reset, see below.
1. Use the  up/down buttons to select the desired item.
2. Press the  up/down buttons to enter or remove the checkmark.
NOTE: When an item is checked, the corresponding parameters will be reset as described below:
SYSTEM SETUP FILES
Resets the System Setup parameters to the original factory settings.
MIDI SETUP FILES
Resets the MIDI settings including the MIDI Setups on the USER tab display to the original factory status.
USER EFFECT FILES
Resets the current Effect settings and the following data:
User Effect Types
User Master EQ Types
User Vocal Harmony Types [PSR-S950] only
User Microphone Setting Memories [PSR-S950] only
MUSIC FINDER FILES
Resets the Music Finder data [all Records] to the original factory settings.
FILES & FOLDERS
Deletes all files and folders including the Expansion folder stored in the USER tab display.
Turns off all the Registration Memory – lights, indicating that no Registration Memory Bank is selected although all the Registration Memory Bank files are maintained.
3. Press the [D] [FACTORY RESET EXECUTE] button to execute the Factory Reset operation for all check-marked items.