Always better if you can provide Computer model & Windows Operating System type information & anything else you think is relevant, e.g. any recent changes made, error messages etc.. ? Does anyone else have access to your computer?   To clear boot set up password (if unknown) you will need to use the 3-pin password jumper on the system board E.g. if your computer is a Dimension 8400 then click here & follow instructions
When I power on my dell it comes up and says need a password ? is there a way to reset this are is somthing gone bad? Is there a factory reset?
boot up problems ask for password