Under certain circumstances Windows XP can get stuck in an loop where it continually asks you to active the product, but the activation wizard tells you that it is already activated.
To fix this download the Windows Product Key Update Tool and then run through the steps below to change the key. Reboot the PC when asked, and you should now be able to boot into Windows.
Be careful though, because I have seen the Windows Product Key Update Tool crash making it impossible to boot into Windows, so always backup first.
You may need a second XP key as the Product Key Change Tool usually won't allow you to update the key with the same key, but you can always use the tool twice to change it back.
You may also be able to use the fix from Microsoft here.
To fix this download the Windows Product Key Update Tool and then run through the steps below to change the key. Reboot the PC when asked, and you should now be able to boot into Windows.
Be careful though, because I have seen the Windows Product Key Update Tool crash making it impossible to boot into Windows, so always backup first.
You may need a second XP key as the Product Key Change Tool usually won't allow you to update the key with the same key, but you can always use the tool twice to change it back.
You may also be able to use the fix from Microsoft here.
Click Yes
Press the Windows Key + U
Click the link to the "Microsoft Web site"
Press CTRL + O in Internet Explorer, then Browse
Set "Files of type" to "All Files", right click on KeyUpdateTool_enu.exe and click Open
Run the Product Key Update tool
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by phyxx
Over 10 years of experience in IT support, programming and fiddling with anything that has an on switch. (more)
