This is issue has resolution as it has been published on Toshiba's Official Support Website. It seems you need to go to an Authorized Toshiba Center. They have a special tool to re-flash your BIOS and it will resolve the issue. I am adding the original text and link for the solution below
New BIOS fixes incorrect power-on password prompt
ACPI, BIOS, Password
P100-ST7111, P100-ST7211, P100-ST9212, P100-ST9612, P100-ST9412,
P100-ST1071, P100-ST9732, P100-ST1072, P100-ST9762, P100-ST9772,
P100-ST9752, P100-ST9742, P100-ST9712, P100-ST9012, P105-S921,
P105-S9312, P105-S6074, P105-S6034, P105-S6124, P105-S6114, P105-S6104,
P105-S6102, P105-S9722, P105-S6062, P105-S6022, P105-S6084, P105-S6064,
P105-S9339, P105-S9337, P105-S6227, P105-S6217, P105-S6158, P105-S6148,
P105-S6207, P105-S6197, P105-S6187, P105-S6177, P105-S6167, P105-S6157,
P105-S6147, P105-S6134, P105-S6024, P105-S6054, P105-S6014, P105-S6004,
P105-S6012, P105-S6002, P105-S931 << hide
Use of any software made available for download from this system
constitutes your acceptance of the Export Control Terms and the terms
in the Toshiba end-user license agreement both of which you can view
before downloading any such software.
The computer models listed above may display a "Password =
prompt when the computer is turned on, even though no power-on password
has been set. If this happens, there is no password that will satisfy
the password request. If the computer is turned off and back on again,
it is very likely that the same password prompt will appear. The
computer will be unusable until this problem is fixed.
the problem has not happened yet, you can prevent it from happening in
the future by upgrading the BIOS to the newest version.
occurrence of this problem on any particular computer is unpredictable
-- it may never happen, but it could happen any time that the computer
is turned on. If this problem does occur, it will be necessary to send
the computer to a Toshiba Authorized Service Provider, who will fix the
problem at no charge to you.
If this problem has not yet occurred on your computer, then click the following link to download and install BIOS version 4.00
. This BIOS displays a power-on password prompt only when a power-on password has actually been set via the BIOS Setup program.
You may also browse for a newer version of the computer's BIOS at pcsupport.toshiba.com.
For more help, see Support Bulletin 98081213 Obtaining downloads and support docs from the Toshiba Support website
the problem has already occurred on your computer, then please make
arrangements with a Toshiba Authorized Service Provider to have this
problem fixed at no charge. To locate a Toshiba Authorized Service
Provider (ASP), please visit Toshiba's Global ASP Locator at http://pcrepair.toshiba.com