Unable to log on to recently purchased used laptop

Hi,

I bought a used laptop online, as I needed it for work for 6 months and didn't want to shell out for a brand new machine.

The laptop arrived, but the seller left it logged in as 'user' and didn't leave me a password.
Upon restarting, it doesn't give me the option to log in as anyone else.
I've contacted him for the password but am yet to receive a response and I urgently need to use it.

Is there a way for me to log on as administrator?

many thanks

Greg

so this is not displayed “Switch User”

you will need another computer to use this method How to bypass Windows 7, vista and xp administrator password

or please read this tutorial by bare foot kid(you will need access to another pc to create a windows system repair disc)How to Reset a Windows Password in Regedit at Boot