Apple required/asked for Credit Card from me to upgrade a Desktop to (I think) Mavericks. It was an old computer that an employee of mine used to use. I logged

Apple required/asked for Credit Card from me to upgrade a Desktop to (I think) Mavericks. It was an old computer that an employee of mine used to use. I logged in, had a look, saw an available upgrade and clicked to install it and - boom - please can we have your CC. I do not like that.