hi i got my new labtop satelite l850 with win 7 home basic and updated to ulimate using cd i have tried to enter my key but geting errors and unable to activate the windows i got problem occurred on activating error code 0xc004e003 after reading i found that i need oem slp key for it but it didnt work users said i have to update my bios or use bios mod can you write me a steps to activate my win ??