if you have a Toshiba Satellite L300 and you would like to restore the system to factory settings (meaning back to the way it was when you first bought it) below you will be able to find the instructions on how to do it.
To reinstall your laptop to the factory settings / “out of the box” settings, please follow these steps. It worked for me, and should work for you.
ALL DATA WILL BE ERASED ON YOUR HARD DRIVE IF YOU PROCEED. YOU WILL NEED TO ENSURE THAT YOU HAVE THE POWER ADAPTER PLUGGED IN. DO NOT SWITCH OFF OR RESTART YOUR COMPUTER DURING THIS PROCESS.
1) Hold down the power button for 10 (ten) seconds to switch off your machine.
Please note: Holding down the power button on the machine forces it to switch off. Any unsaved data will be lost.
2) Press and hold the 0 (zero) key and at the same time, tap the power button once to switch on your notebook.
3) When the machine Starts beeping; release the 0 key.
4) When prompted by the warning screen; select Yes to continue with the system recovery.
5) Select Recovery of Factory Default Software; click Next.
6) Select Recover to out-of-box state. Click Next again.
7) Click Next to Start recovery.
Source and credit to=> Reset toshiba laptop to factory settings [Solved].