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To reduce software piracy and to make sure that all Microsoft customers receive the product quality that they expect, Microsoft is now including product activation technology in several products. This article defines product activation and describes when and how to activate a Microsoft product. It also explains how to contact a Microsoft Product Activation Center and contains additional product activation resources.


  • Microsoft product activation telephone numbers are not listed in this article. There are many regional Microsoft Product Activation Centers worldwide. Use the Product Activation Wizard to make sure that you are routed to the correct regional Product Activation Center.

  • You can activate online or call the Product Activation line and use the automated menu. However, assisted support is no longer available for activating Windows XP or Windows Vista.

More Information

Microsoft uses product activation to reduce a form of piracy known as "casual copying" or "softlifting." Casual copying occurs when people share software in a way that violates the Microsoft Software License Terms. For example, when a person buys Windows XP, that copy of Windows XP is primarily licensed for use on a single computer. Without the purchase of additional licenses, that copy of Windows XP may not be installed on additional computers. For example, if that copy of Windows XP were to be shared with another person and installed on that other person's computer, that would constitute casual copying. However, with most software licenses, you are allowed to reinstall and activate the software on the same computer an unlimited number of times. To make sure that you are using your Microsoft software appropriately, see the Microsoft Software License Terms or the product use rights for more information about that specific product.

Casual copying accounts for a large part of the piracy losses that the software industry experiences. If software piracy were to be reduced, the software industry could invest much more money in product development, in product quality, and in product support. This would lead to better products and more innovation for customers.

How product activation works

Product activation is a simple, straightforward process that is completely software based. It requires no hardware add-ons or any other external tool. In most cases, the only information that is needed to activate a product is an installation ID, which is created by the software itself. The information that is collected during activation will not be used to personally identify the user.

If you activate your product over the Internet, product activation takes less than a minute. When you activate your product in this way, the product itself will do most of the work. Very little user effort is required. If you would rather activate your product over the telephone, you can do this by contacting the regional Microsoft Product Activation Center.

Important Product activation does not track users of Microsoft software in any way. Its sole purpose is to activate legitimate licenses for Microsoft software.

When to activate a Microsoft product

Software that is bought in stores or as part of a new computer that is sold by an OEM must be activated. As mentioned earlier, product activation is easy, and many users only have to activate a product one time during the life of the product. However, some products may have to be activated again if the product is moved to another computer or if significant changes are made to the computer on which the product is installed.

Note OEMs may activate the software at the factory before they deliver the computer to the customer. To make activation convenient, Microsoft products do not have to be activated immediately after they are installed. You can start Microsoft Office up to 50 times before you have to activate it. For Microsoft Windows, you have 30 days from the first time that you use the operating system before you have to activate it.

How to activate a Microsoft product

To activate a Microsoft product, select either the Internet option or the telephone option in the Product Activation Wizard.

  • With Internet-based activation, Microsoft servers process the activation and activate the product.

  • With telephone-based activation, you activate your product by contacting a Microsoft Product Activation Center and following the steps that are provided by an automated telephone system.

Additional information

300273 Cannot activate OEM edition more than once in Office XP

293151 Description of the Office Activation Wizard

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