Delete all passwords from my acer aspire laptop

[Guest]

Hello,
i have an acer aspire laptop, there was a previous owner that i bought it from, i cant download flash player or absalutley anything as its asking for an administrative password, i dont no it and iv removed battery ect, but n othings working this user that doesnt have this laptop anymore had holds over everything and its getting me down, please help.

 

[frozenlead]

You could ask him for the password. Or reinstall windows. If the administrator account is unprotected, you can login in safe mode and delete the password as well.