Try these steps, hope they will help you:
1. Copy all your files and documents to an external storage device.
2. Shut down the computer.
3. Turn the PC back on and hit the F8 key repeatedly until the Advanced Boot Option Screen appears.
4. Click "Repair Your Computer" if you are not already on it and then press ENTER
5. choose your country and click OK
6. On the "System Recovery Options Screen" click "Restore Application" which is the last option.
7. Follow the on-screen instructions
8. When prompted, click on "Full Factory Recovery"
10. Click "Yes"
11. you will notice for a while it seems like nothing is happening, give it some time.
12. After some minutes, recovery will complete and you click "Finish"
Toshiba laptops from mid 2007 onwards dont have a recovery disc supplied with a purchase of a laptop. Instead, Toshiba has added a hidden partion on the hard drive which contains the same files on a recovery cd / dvd.
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.