Windows operating systems like Windows Vista give users the flexibility to change their product key if needed. The product key is the unique identification number assigned to every genuine copy of the Windows operating system. The option to change the product key in Windows Vista could be easily found by accessing the Start menu. One needs to access Properties of 'Computer' and change the product key at the relevant place. If the computer is connected over the internet then it checks automatically for the validity of the key. In case the user is not connected to the internet then the activation can be done via a phone.
Like XP, it is possible to change the license key for your Vista. However, reactivation is required.
To do this:
Go to Start> right click Computer> Properties
At the bottom of the page, click Change product key
Enter the new key in the Product Key and click Next
At this point, you have two options:
1. If you were connected to the internet, activation is automatic and a window will tell you if your key is valid or not.
2. If you were not connected to the internet, then you activate Windows by phone. Follow the instructions in the setup wizard. It is advisable to install Service Pack 1 for Vista for a complete list of phone numbers.