How to i switch my operating system back to Vista if I downgraded it to XP?

My computer needs repair and the manufacturer won't do anything until i change it back to Vista!

How to i switch my operating system back to Vista if I downgraded it to XP?free adware remover

You have to put the vista CD back and install that.

How to i switch my operating system back to Vista if I downgraded it to XP?internet security 2006

yes the only thing you can do is reinstall it.

theres no back button on your computer :)