Dear Robert Devine,
Thank you for reaching out to the Microsoft Q&A.
First, for your online security, I have removed the Windows product key from your post. It is very important that you do not share product keys in public forums.
The main challenge is that, as of 2025, the original automated phone activation system for Windows XP has been decommissioned by Microsoft. The phone numbers displayed on the activation screen in Windows XP itself will likely no longer work.
- Calling the current MS activation number for a product still in support (e.g. for activation for Win7) and choosing "Other Products" in the voice menu. Refer to this link Volume License Key Phone Numbers | Microsoft Volume Licensing
- When you call, you will likely get an automated system. This is the most important step: Do not enter or say anything when prompted. The automated system is not equipped to handle Windows XP. After a few moments of silence or if you keep saying "agent," the system should transfer you to a human support agent.
- Explain your situation clearly and follow the agent's guidance.
Please be aware that Windows XP has not received any security updates from Microsoft since 2014. This means it is extremely vulnerable to modern viruses and malware. Since you are keeping it offline, the risk is lower, but you should still be very careful about connecting any USB drives or using old discs that could contain malware. Under no circumstances should you ever connect this PC to the internet.
I hope this helps you get your classic gaming PC up and running again!
To assist others who might have similar questions and to help us improve our support system, we kindly encourage you to "Accept the answer" if it successfully addressed your concern. Accepting an answer lets other users know that this solution worked for you, and it also helps us track the effectiveness of our support efforts.