Goodday I bought laptop hp compaq nw8240 but cant go into bios. Wanna reinstall windows, but shows administrator password. Can u pls help to unlock or reset bios password . Thanks

don't trouble yourself
try this password if you are using compaq
75681807

Try a software called !BIOS or see if you can find Hieren's Bootdisk

HP Spare Key can be used to reset BIOS password. It is provided by HP Corporation. So when you forgot BIOS password on HP computer, just download it and get perfect BIOS password reset.
How to reset HP bios password with Spare Key or other ways?

Please refer to reset HP Elitebook password. In this passage, you also can learn how to reset Windows administrator password easily.
http://www.isunshare.com/windows-7-password/reset-hp-elitebook-password.html

Do you want to know about bios power-on password reset on HP 6720s?
Turn to Reset HP BIOS/Administrator Password
It shows you how to reset HP BIOS password with SpareKey, and how to reset HP administrator password with effective Windows Password Genius in just 2 minutes.

Get a video learn how to use it:
http://www.youtube.com/watch?v=-vrVcFaUATg&feature=youtu.be

o a google search for windows password killer or lastpass

Actually, if you want to remove BIOS password on HP laptop or PC, there is an effective tool Spare Key available for you. It is provided by HP Corporation. At the same time, if you prepare to remove HP administrator password, you can have a try to use Windows Password Genius. Choose appropriate version based on your computer operating system, Windows Password Genius Standard/Professional/Advanced.

if is the windows lock administrator password press F5 and go to safe mode and remove password from control panel if is the bios password remove the battery from the motherboard for 5 second then put it back

to get bios password reset: http://www.windowspasswordsrecovery.com/articles/computer/how-to-reset-bios-password.html

Nope, if you do not have the bios password, the only way to reset it is by accessing the motherboard, removing case and keyboard, and either removing Cmos coin shaped battery for one second, or bridgeing the Cmos reset jumper (that interrupts contact to battery, same as removing battery).

First, DON'T SHORT ANYTHING ELSE OUT!
Now, tell me how one sets a bios password, then just forgets it?
If you can prove ownership on a laptop as new as a DV4000, there are plenty of posts out there describing the proceedure for recovering the system. Occasionally even HP will helpout legitimate owners in situations such as this.
I'm sorry, but this isn't the forum for this particular problem.
Good luck