Hello
All updates they are available on Toshiba website are pretested by Toshiba so there is no known issue.
Fact is something went wrong during BIOS update, maybe you did run some background applications like antivirus, firewall or something else. This can affect the BIOS update process.
Anyway, now it’s too late and the only way to get rid of this is contacting an authorized service provider in your country. The guys can reflash the ROM module that is necessary in this case.
Here is a list of ASPs:
http://eu.computers.toshiba-europe.com/ > Support & Downloads > Find an authorized service provider