This sounds as if the BIOS Password somehow got set. In the newer laptops it's easy to get to the CMOS battery, pop it out and wait about 5 minutes and then put the battery back in. Pay attention to how the battery goes back in by looking closely before you pop it out.
Unplug the power supply cord to the laptop. Remove the laptop battery. Push and hold the power button for about 5 seconds. This PDF
will show you the location of all the 'doors' on the back of the laptop. Scroll down to the last page. The CMOS battery
looks like a large watch battery.
I also found this at another site and it's worth checking the info on the Toshiba site. If this is true this is a known problem and Toshiba has a fix for it: "For all you so called arrogant techs out there who have assumed that
most of the people who have had problems with Satellite A135-s2276 have
stolen their laptop check out your info from Toshiba....There is a known
problem ...A KNOWN PROBLEM pertaining to the password issue. There is a
defect on several of toshiba models. There is no password...the bug in
the bios causes the password prompt and toshiba has a fix for that
problem which has to be applied before the problem occurs which can be
downloaded from their website. Also if you are now experiencing the
password prompt problem Toshiba....yes, Toshiba is correcting the
problem at no cost to the customer. The website has instructions on how
to have it done free by Toshiba and shipping info because you have to
ship it to them they have acknowledged the problem. I had mine
corrected....and it work just fine.
This being said, try the CMOS battery reset first and if that doesn't work, please contact Toshiba. I'm not positive but you may have to ship the laptop back to them for the fix.