I want to get the password of the admin BUT NOT RESET IT.

The problem I am having is every time I want to install any piece of software, it asks me for the password of the Admin, i.e. my dad.

I have tried keyloggers but either they cost money or require installation. You see my problem?

Maybe I could do it through some linux live cd?

I dunno, you're the experts.. Help me out.

Thanks in advance