In these cases, you will have to call Microsoft and do an over the phone activation. If you have swapped out hard drives, graphics cards, memory, etc over time, then you might run into problems when you try to reactivate Windows online using the same product key.

Normally, the online reactivation will work just fine as long as the hardware on your computer hasn’t changed very much since the OS was originally installed and the version of Windows is exactly the same as the version that shipped with the computer. If you are planning on doing a clean install of Windows on your PC, you will more than likely have to reactivate Windows, either online or over the phone. Where you from anyhow? Are you in the sticks or near a city? Repost.You can do this in a 'legit' way yunno. You can do a vice versa with home edition but really sooo much easier to get a professional copy. Then 'Change key' and your WGA alert will allow you to update. Simply change over the key to a valid one. (For professional) When you get a VALID Win Xp key, for the profesional. Use the usual serial number that is invalid. YES you can upgarde and NOT lose your files on home edition. Anyhow, I would 'upgrade' to a professional version. This is why I like Prefessional edition over home. This wikiHow teaches you how to temporarily remove the Windows activation notifications and watermark from an unactivated version of Windows.

Per attivare Windows con un solo click, scaricate il programmino WPAkill, salvatelo sul desktop, riavviate la macchina, al boot premete F8.

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