I recently tried to reset my PC to fix some issues with the brightness settings. I opted for the option to "Reset but keep my personal files" and everything seemed normal. However, after rebooting, my computer went into a sort of demo mode, telling me to activate Windows. Whenever I try to activate it in settings, I get an error saying I don't have a valid product key. I think the product key was originally installed on my PC, but it seems to have been erased during the reset. I can't find any product key sticker or manual, so I'm stuck and can't customize my setup!
3 Answers
I've had a similar issue before. My laptop activated automatically after I connected it to the internet for a couple of days. You might want to try that and see if it works for you!
Did you buy your PC from a specific retailer? It sounds like they might have used a sketchy method for activation.
Your product key probably isn't actually deleted because it's either in the BIOS or linked to your hardware ID on Microsoft servers. If your PC is from a store, you might have a grey market key that can only be used once. If it’s a prebuilt like a Dell, the key should be in the BIOS. You should avoid doing a 'reset' because that can lead to activation problems. Consider wiping your drive and doing a clean install of Windows instead. Just make sure to back up your files because you'll lose everything. Use the same edition of Windows that was originally on the PC, and it should activate automatically if the key is still valid. If it doesn't, you may need to buy a new key.

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