Product Activation is required for all licenses purchased through retail distribution. Some PC manufacturers, however, will activate the Microsoft software in the factory so the end user does not have to do so. Customers will be notified on the outside of the packaged box when they acquire a retail version of the product. If they have not activated the product within the specified timeframe, they will need to do so to continue using the product. Microsoft Product Activation is completely anonymous and no personally identifiable information is collected.
Activation is different from product registration.
If they want, customers may voluntarily register their product by providing their name and contact information. Registration is for those customers who want to receive future communications on product updates, service releases and other special offers. Any information provided to Microsoft remains secure and private and is used only for the purposes specified by the customer. Windows Welcome will guide the user through activation. Users who choose to skip activation during setup will be reminded periodically during the following 30 days to activate Windows.