This a brief guide to how to activate Windows XP or check if your Windows XP is activated.
Start Windows XP Registration Wizard simply by entering the command given below,
open the Run dialog box
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Read if applies to you:
Microsoft Windows XP Registration Wizard appears, then follow the instructions shown.
Activation helps verify that your copy of Windows is genuine and that it has not been used on more computers than the Microsoft Software License Terms allow. In this way, activation helps prevent software counterfeiting. With an activated copy of Windows, you’ll be able to use every Windows feature.
Activation and registration are not the same. Activation is required, but registration is not. Activation is the process of ensuring that your copy of Windows is used according to the Microsoft Software License Terms, whereas registration is the process of entering information (such as your e‑mail address) to sign up for product support, tools and tips, and other product benefits.