No, you cannot reuse a written-down Windows 11 Home OEM key on the same computer after switching to Pro.
No, you cannot reuse a written-down Windows 11 Home OEM key on the same computer after switching to Pro.
I recently purchased a Windows 11 Pro key but am uncertain about its reliability. I’d like the flexibility to downgrade if the key fails or expires, similar to a Volume licensing key. I plan to save the original OEM key in case I need to revert to it. Does this technically comply with OEM rules since I’m using it on the same machine?
If you bought it as a standalone key code, you should likely be okay. However, if it was an "upgrade" code, there might be issues. It would be wise to confirm the key is linked to your MS account and then remove it before updating to the pro version. I’m not sure how the Hardware ID fits into this.
Where did you purchase the key? If you obtained it from Microsoft or a prominent electronics store that sells PCs, then there are no concerns about its reliability. However, if you acquired it from other places such as eBay or Kinguin, I wouldn't even consider using the key.
Concerning OEM licenses, they are tied to the motherboard on which the computer was activated. It doesn't matter whether another license is installed on the same board; you cannot transfer the license to a different device.
I think it's quite amusing how many YT influencers have shifted their opinions on this topic. A few years back, very few would recommend using a grey market key. Back then, most influencers strongly opposed such suggestions, often criticizing those who made them. Nowadays, it seems many of the same influencers are taking money from sponsorships or offering discount codes for these keys. In some instances, they even go to great lengths to fake situations, like pretending to call Microsoft, just to demonstrate that it's acceptable. It's clear to me that Microsoft is aware of this trend, but their current response suggests they prioritize data collection over the cost of licenses. This shows that metadata remains more valuable than the actual spending.
I would argue that this isn't a recent thing about Microsoft not caring about people trying to either not pay for a license or getting it cheaper.
Yes you could say now it's about data mining, but more importantly for a software company, it's about market share and relevance. If people only know how to use Windows, that keeps them from using Linux or macOS because unless something really egregious happens, it's very hard to change once you're in one thing. And if people only know how to use Windows, then large volume customers will be pretty much forced to buy Windows machines.
Also it's more cost effective to gut a company of its money than it is to go after grandma because she didn't know her grandson installed Windows with an iffy key.
The influencers have been promoting the inexpensive keys for a long time because they receive payment for it.
As you note, TPM has consistently been an issue for years, and PCs from the 8th generation onward can still function properly with a single one active or simply powered on.