To everyone doing a clean Windows 10 install and been getting an Error Code 0xC004C003 for several days with out activation.
I have tried several times to activate my Windows 10. I had several systems that I upgraded Windows via Windows update etc. Upgrading I was able to activate with no problems every single time. After I upgraded and activated I did a clean install from a USB created with Media Creation Tool from MS. No matter what I did the clean install wouldnt activate and would give an Error Code 0xC004C003. I made sure that my Windows 10 upgrade was activated first. I logged into an MS account once I installed Windows 10 thinking that would help. Nothing worked but I kept trying. Heres what I did that now has since worked on the two systems was getting the Error Code 0xC004C003 for days.
1. First, I removed all Windows 10 listings from my "Devices" on my Microsoft account. Each computer with Windows 10 gets listed there. They get added back once you login again.
2. Next I started from scratch. I reinstalled Windows 8.1 clean. Now this time something different I did that I hadnt done before was I logged into my MS account on Windows 8. I historically had been using "local accounts".
I also made sure the install was activated by going to the "CMD" prompt and typing "slmgr.vbs /ato".
3. Once started logging into Windows using my MS account and was certain Windows 8 was activated then I started the upgrade process. I used Windows update on one computer and Media Creation Tool on the other computer to do a Windows 10 Upgrade. Again once Windows 10 was installed I made sure it was activated by going to the "CMD" prompt and typing "slmgr.vbs /ato". I also then made sure that I was logging into Windows 10 with my MS account. For giggles I restarted the computer a few times to make sure it synced with the activation servers etc. I even did a few quick updates for the hell of it.
(You can login to your MS account and now see your computer listed under devices.)
4. Next is when I finally did a clean install of Windows 10. Again I used a USB from the Media Creation Tool.
During the install I made sure to login to my MS account. Viola it was automatically activated instantly.
Thoughts: I have two theories about this. The two things I did different were as follows. Again as I pointed out I historically was using local accounts so while on Windows 8 perhaps logging into Windows 8 via an MS account logs the Hardware and the licensing information on the account. It does not show under devices like Windows 10 installs but it could however be logged behind the scenes. As I type this out I wonder then what that means for Windows 7 users. Perhaps those upgrades arnt the ones experiencing the issues. I dont know as I havent done a Windows 7 to 10 clean install.
My next different action was using the "slmgr.vbs /ato" command both when I installed Windows 8 and when I did the upgrade to Windows 10. Either way I did this exact process twice (very time consuming lol) and it worked on two computers that I did upgrades and then clean installs before but wouldnt activate even after 12 days.
Im sure someone somewhere will find this usefull so I knew I had to post it.