You may have "wiped" the factory backup partition, but assuming you haven't, read the post with green header from
danny2000 in this thread:
http://www.tomshardware.co.uk/forum/86067-35-restore-toshiba-back-factory-settings
If the backup partition no longer exists, you can order a set of backup media direct from Toshiba via this page:
https://backupmedia.toshiba.eu/
I ordered a set six months ago, they charged me a very reasonable £15 (UK)