Unlike Windows XP and Vista, failure to activate Windows 7 leaves you with an annoying, but somewhat usable system. When you try to install the same copy of Windows on more than one PC and then try to activate online or by phone, the activation will fail. No two computers will have the same hardware signature. Information from your video display adapter, SCSI and IDE drive adapters, processor type and serial number, hard drive serial number and your network adapter Media Access Control address are combined to form a unique identity for your computer. Such a link should prevent the same copy of Windows from being installed on more than one machine, as was possible with earlier versions of Windows.

Instead, the goal of Windows activation is to establish a link between a licensed copy Windows and a specific computer system via your product key. It is also different from post-installation registration. Activation differs from the installation process that requires a product code.

After installing Windows you are likely to get a notification asking you to activate windows.

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