All Toughbooks pre-2010 required a "recovery" dvd
in order to reset the unit to Factory Defaults.
In Canada these recovery dvd used to be free,
but after 2010 they started to charge for them.
If you still have a Windows sticker or COA on the
underside of your Toughbook then you can use
a Windows CD or DVD that corresponds to the
sticker and then enter the 25 digit code.
If you do it this way, you will be required to download
all the drivers manually from the panasonic website.
This is the Toughbook and Toughpad website for drivers:
http://pc-dl.panasonic.co.jp/itn/default.html
Good Luck and Happy New Year 2018.
Regards from Richard, Montreal Based Panasonic Canada
Authorized Toughbook Dealer sibce 1989.