i am rebuilding the OS from scratch
I'm not sure what you mean here
If it is the original hd you could try the recovery partition,;
To access the recovery partition do the following...
Power off the laptop.
Hold down the 0 (zero) key and turn the laptop on. Keep holding down the zero key until the TOSHIBA logo appears.
Start tapping the zero key repeatedly at this point.
Stop if the unit beeps or when the TOSHIBA logo disappears.
The screen should flash HDD RECOVERY MODE
for a second and then it will load the Toshiba recovery program right from the hard drive.Note that this erases all data, and reloads all factory default software.