See if you turned on "FN Lock".
For windows 7:
Run the HW Setup program by clicking Start -> All Programs -> TOSHIBA -> Tools & Utilities -> HWSETUP.
The HW Setup dialog contains a number of tabs. Click the "Keyboard" tab.
If Special Function Mode and Standard F1-F12 Mode choices are presented, select Select Standard F1-F12 Mode. If the Special Function Mode and Select Standard F1-F12 Mode choices do not appear, your particular Toshiba laptop does not need this adjustment.
Click Ok
Close the HW Setup program.
For Windows 8/8.1/10:
http://www.mytoshiba.com.au/support/item/695