Hey guys. Just built a r3 2200g pc. Asrock ab350m Pro 4 matx motherboard. I installed windows 10 home and signed with my microsoft account, which is an insider account, so it normally activated automatically. This time it's giving me activation error code 0x803f7001. When I look at the devices under my account online, it says "to be filled by OEM" is that why I can't activate? Any thoughts?
There is an additional part to the activation that is not normally mentioned as usually people re-activate Windows 10 on the same computer. A unique hardware identifier is created and attached to your Microsoft account.
So what's happened is that the activation server probably thinks you are re-activating the same key on another PC as generally speaking it's another PC as the motherboard has changed. Or the activation server is done or experiencing issues - won't be the first time - if the issue persists for a week or more check the solutions section below.
To provide some context on change of activation mechanics:
When the Windows 10 upgrade was initally offered for free you were given a new key automatically however that mechanism changed. I know this for a fact because when I upgraded my laptop to W10 and it was given an new key - without the use of a new Microsoft Account.
This was done to encourage pirates to get legit installs and thus removing the security obstacles of not having the entire Windows 10 Userbase upto date - which leaves everyone vulnerable due to zero day exploits and use of unsecured/un-updated pcs as data nodes to spread malicious malware to other PCs.
But as usual those who were not of aware of such ramifications complained and there was a backlash over the decision to get pirates onto legit installs. It also meant developers would have had a larger valid pool to monetise... but it is what it is.
Solutions:
The simplest way is way to use sysprep however I do not think that tool is available on Windows 10 home. What sysprep does is remove all hardware association to a windows install and reverts it to the windows out of box experience (commonly called in tech jargon as OOBE).
If you do not have access to Sysprep - you have two remaining options.
1)Contact Microsoft and explain the situation - this also means you will not be able to use your previous hardware configuration. They will be able to generate you a new key and revoke the old key.
2)Obtain a new serial key - once obtained go to Settings -> Update and security -> activation -> change product key. This way you do not have to reinstall the entire o/s or mess around with command prompt.