If the Portege/Dynabook Z30-C has a Bios Supervisor password activated, and you cannot remove it via the Window Supervisor utility tool, then try the following :
Power the device down fully
Press and hold the F2 key
While holding F2, press and release the power button
The device should now ask for the Supervisor password
Enter the Supervisor password
The device should enter Bios in Supervisor mode
This is confirmed to work on the following models :
Toshiba Portege Z30-C-16
Dyanbook Portege Z30-C-16
The Portege/Dynabook Z30-C doesn't have a individual battery.
Instead, the main battery supplies power to the BIOS.
Remove the main battery to clear CMOS. To remove the battery, follow the disassembly guide on myfixguide.com :