What if I required a clean install after a year has passed
Charles (MSFT) has stated the following:
1. "Once you upgrade to Windows 10 successfully using the free upgrade offer, you will be able to clean reinstall Windows 10 on the same device during and after the free upgrade offer period without having to purchase Windows 10 or having to go back to the prior version of Windows that you upgraded from."
2. "When you upgrade to Windows 10 from an Activated, Genuine, Qualifying OS (Windows 7, Windows 7 SP1, Windows 8, Windows 8.1) we register a Windows 10 Entitlement when the Windows 10 machine Activates and is on the internet.
This is not tied to your MSA, it is tied to your hardware Id which is mostly based on your motherboard fixed components. (no problem swapping that hard drive)
That fact we tie the license to the hardware is no change from XP, Vista, 7 or 8. What has changed is that when we upgrade you don't get a 5x5 key, but we register a Windows 10 entitlement via our licensing service. If you in years later need to re-install or clean install Windows 10, you can download media (which we have made easy to get now), install, skip entering your product key and on first boot when you connect to the internet it will match your Hardware ID, retrieve your Windows 10 entitlement and activate your system.
What we are getting away from is users having to squirrel away 5x5 keys forever and allow users more control over when they clean install or re-install. But its super important to upgrade that first install because we check the status of the down-level OS and grant that Windows 10 entitlement when Windows 10 activates."
3. "So every OS license is tied to the hardware its activated on.
We currently have a process where users can ask for an override if they have to change out hardware that changes the ID of the system. Its a process that contacts Activation Support, and MS in either an automated way or a manual way determines if abuse is happening and allows the exception. If your Windows 10 system goes out of hardware tolerance, the same thing will happen though the interactions might change over time. During the Preview Period, we will encourage folks who upgrade to return to their original OS, Activate that (request an override) and then upgrade and get that new Win10 license registered; I say encourage and not require.
Its a balance. For 10 we have changed the balance a bit. We know users like to swap out hardware, so we moved the ID more to fixed components. The idea being that fewer people will now need to contact us after upgrading their hard drive (I'm crazy about taking old systems and putting SSD in them to see how well they run). The flip size of that is we are more dependent on that big square thing in the center. We hope the result is fewer people needing to contact us and an easier time telling when piracy is happening compared to just people like us who like to swap out components; including Motherboards. (I've got a DELL Vostro 410 that sits hangs at the bios, sometimes it will boot and sometimes not. I picked up a pulled MB with a better CPU on eBay and will swap out when I have some down time. I'm going to make sure I have Win10 on the system so I can watch the process and myself walk through support.)"
4. "So getting a product key would not change the license behavior. Since XP it has always been the case that your license has been tied to your hardware. In fact, for Win10 we have made it easier to change the more common components without pushing it out of hardware tolerance. And, just like previous OS, if you do fall out of hardware tolerance you can contact MS Support and ask for an exception. So really didn't change. Product Keys are pre-internet technology. I know we like to have them and see them (me too, I work on MS and I have XLS of my 5x5s and what machines I use them on.) That said, Microsoft wants to move to a keyless license world. Tons of calls and problems exist because people can't read they key, miss-type the key or just misplace the email or paper its on."
5. " Couple of things:
1.When you upgrade to Windows 10, you do not get a unique Win10 Key; its generic.
2.Your Windows 10 entitlement is registered against your HardwareID and not your MSA. Plenty of users run on Local Accounts and we register a Windows 10 entitlement for them to.
When you upgrade on a Genuine, Activated Windows 7, Windows 8 or Windows 8.1 PC to Windows 10. The Windows 10 Activation Process determines the previous OS was Genuine and that the Genuineness matches the HardwareID so we log an Entitlement for that HardwareID for Windows 10 to our Store Activation Service. When Windows 10 says it has Activated, then this has happened. You can also check. In Win10 search on Activate and see the result "See if Windows is Activated"
If you need to wipe the drive (or replace) at a later time and clean install Windows 10, Install from media, skip entering a product key and when the device goes to Activate, it will compare the HardwareID, pull down the Entitlement that already exists and Activate. Yeah!!!"
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For those wishing to wade through the 8 pages of Q and A's go here
http://answers.microsoft.com/en-us/...s/ef8bdcc0-b84b-4c16-a690-1bf0aa803ab8?page=8
The above responses are consistent with the ongoing discussion on similar topics with the Windows 10 Team (Program Management, Licensing, Product, Support, etc.) in a variety of private forums, groups and listservs for MVP's and MSFT Employees.
http://answers.microsoft.com/en-us/.../578d0b7f-57e4-4893-b9d1-6cfac0d6290a?page=84