I Lost My Windows 10 Product Key After Windows 10 Reinstallation

Copper Contributor
When I first bought my laptop and opened it, the Windows 10 product key was automatically activated. I am using my computer for almost 2 years now and never encountered a problem about this.

Disk Drive D being sometimes missing on my computer led me to reset my laptop. After choosing the first option which enables me to Factory Reset my laptop but keep my personal files, my Windows 10 is still activated.

This reset had solved my problem of Disk Drive D sometimes disappearing. But another problem arose. I can't install Office 365 properly now, it always gives this ERROR CODE 30015-11 (3221225506). I did what I could do to uninstall it properly and install it again but to no avail.

I resetted my laptop once more choosing the second option of erasing everything on my computer. But I was stuck at the "hi there" part for a couple of hours (my laptop keeps restarting and going through this "hi there" loop) until I finally found a solution and enables to get past that loop by writing something on the command prompt.

In the desktop, I noticed a "Windows 10 Home" word written below my screen at the right side. I checked the settings and I saw that my Windows 10 product key is gone.

I tried installing Office 365 once more but it still went through that error.

*Sigh*... The reset was supposed to be a way to solve my problem but it just added more.

By the way, the second reset which will delete all of my files did not work. My personal files are still in there.

Any help would be appreciated.

I hope I can still use my lost Product Key.
1 Reply
were you signed into Windows 10 with your Microsoft account?
if you were, your product key must have been added to your MSFT account for future use.

Find your Windows product key

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