Windows 10: Win 10 Activation failed (Error code: 0xC004C003)

I already went through that struggle too man...
Turns out, only way to fresh install and get activated is following 2 simple rules we all messed up:
1) Upgrade from 7/8.1 to 10 and reach the desktop, making 100% sure windows is activated before fresh installing
2) Skip everytime Windows 10 asks for a product key during installation. The key everyone finds with keyfinders is actually just a generic key, everyone's copy gives the same values, and it's worth jack to Microsoft. Entering that during installation guarantees you'll never get activated.

So, if you've already upgraded to 10 from a past OS, and your fresh install still isn't activated, you might not have to go all the way back to 7/8.1. Just try fresh installing again without entering any product keys. As soon as you hit the desktop, windows will automatically activate now, and a product key is entirely unnecessary. Product keys are only needed for retail versions of Windows 10, and the OS won't check to see if your PC is liable for a free upgrade activation.

So yes, bite the bullet people.
Also forewarning, my future installs were glitchy, and cortana wouldn't search and find any of my desktop apps on a local account. I had to log into a Microsoft account for her to even do her job at simply searching for my installed programs
No amount of indexing or registry editing solved a thing. Microsoft is really playing hardball when it comes to Microsoft accounts this time...
As soon as you log into a Microsoft account, you can also never downgrade to local again with that account or ever delete that Microsoft Admin account, or Cortana breaks her searching again... forever for that user.
It's as if Cortana ties your index with your Microsoft account, and switching back and forth permanently glitches a user account. Took me 3-5 Windows Installations to get her to just search correctly, and I'm so sick of it. Treat Windows 10 like a burning fuse for now, don't get too carried away with account sign-ins, because it surely isn't ready to take well to it.

This is just personal experience, and not all people have this... but decide for sure if you want to use a Microsoft account.
I for one had no choice, as all local accounts on all installations except my very first clean boot have bugged like this (so weird, I wiped my drive between every install, and local accounts after my first fresh install never found any installed apps but Windows Apps and apps from Windows Update.)

You can log into a microsoft account without a password as well, just have to go old school and
use "control userpasswords2" in an Administrator-allowed Command Prompt window.
My Microsoft Account feels like a local account with Cortana's benefits thanks to this, besides Microsoft mining every bit of metadata they legally can from me...

Takes you straight to a checkbox, just make sure you enter your Microsoft Account password when confirming the checkbox, and not your local password, or Windows 10 gets confused at log in, and makes you sign in anyways.

 

i've also been siting here unactivated since 3 days ago.. there's no Activate button and the error says "Key Blocked"? i thought we could do clean installs after successfully upgrading?

i called Microsoft and they're claiming "You can never do clean installs, only upgrades"?

i also asked about Hardware ID being saved after successful activation and they said nope?

anyone done a successful clean install lately?
i did it successfully 6 days ago..

but now the Activate button is gone.

 

Did you upgrade to Win10 and get that to activate first before you did a clean install. You have to do that first.

 

yes

i made sure of that.? there's no "Activate" button.. which is weird. i remember seeing it the first time i did a clean install.

 

Check in the settings:

 

thanks.. the "Activate" button doesn't appear.
it just says "Key Blocked".

 

Ok i have decided to bite the bullet and start from scratch again and reinstall Win7,what would be the best way of doing it.Insert the disc into pc while it is already on and run from the autorun,boot up with the disc in pc and run from boot up,or insert disc in pc then access disc rom drive file and click on the setup.exe?Thank you for any advice

 

Turns out, only way to fresh install and get activated is following 2 simple rules we all probably messed up:
1) Upgrade from 7/8.1 to 10 and reach the desktop, making 100% sure windows is activated before fresh installing
2) Skip everytime Windows 10 asks for a product key during installation. The key everyone finds with keyfinders is actually just a generic key, everyone's copy gives the same values, and it's worth jack to Microsoft. Entering that during installation guarantees you'll never get activated.

You never actually have to click an activate button. If you clean install and click the skip button everytime it asks for a product key during your installation, Windows should recognize your PC if you have upgraded at least once, and will autoactivate.

If you skip the product key entry during the clean install and are still not activated when you finally reach the desktop, you may have actually go back to 7/8.1 and upgrade again, as your upgrade may have never been verified and properly activated. Though you successfully clean installed once before you said, so I don't have a clue why you still aren't activated automatically.

If you're given an error code and information, copy/paste or type it our for us word for word, others might have the same thing.
"Key Blocked" usually shows up if you tried to enter a product key during the installation (as I once did), as non-retail Windows 10 users like us don't use a product key from the disc packaging. If you try to manually type a product key in, Windows 10 will never try and auto-activate. It will always ask for a retail product key unless you reinstall and never give it a code in the installation steps.
Windows 10 for free users authenticates on its own by recognizing your hardware. Unless you swapped out your motherboard between your last successful clean install and now, you should have no issues. Windows ties itself to your mobo and possibly CPU, as that's what it considers a valid computer. Using a different mobo/cpu after your first successful upgrade from 7/8.1 to 10 will require you to either buy windows 10 or upgrade a different 7/8.1 copy that never has been upgraded before on the new hardware so it registers your copy to your current configuration.

Don't waste time with Microsoft support, half of those on support have no clue. I've called twice. One told me wait 24/48 hours (actiavation servers weren't my issue). Another told me I'd have to upgrade again. They were partly right, but not once did they give me the heads up that I wasn't supposed to enter any product keys.
That's what these forums are for.

 

I did a clean install using the media tool all went well no problem until I got to the activation part, over a week and still can't activatate

 

i wrote a tutorial after posting this..
i must've upgraded/clean installed 20 times already.
i've been at this since last week..
finally figured it out yesterday *Smile

Read my Tutorial here.
- hope it helps you.. i know it sucks.

 

Thanks.. I'll give it a read.
Jeff

 

Hi, everyone. This is my first post but I had awful issues with updating from Windows 7 Home to 10. I ended up using chat option with Microsoft techs. 7 hours with the first tech who couldn't get it to install, installation kept crashing with error messages so the tech handed it to a level tier 2 tech, who was able to get it to install after another 6 hours of control of my system. However, it would not activate. The tech was supposed to contact me back, he did do this, twice but left me hanging for hours each time. It was to activate 10. I contacted them again and was told it would fix itself in 24 to 48 hours. If not, to contact them back. I did contact them back and the person in the chat..disconnected after asking me to explain everything from the start. I was really not happy with that. The next tech had me go through it all ...again. Only to tell me that a tech would call me in 1 to 2 hours which never happened. I waited for that call all day. So I posted to the Microsoft forum, all of these issues and a tech responded with some hopefully useful information that I wanted to pass on...to everyone I can find on forums with this activation issue. I hope it helps you. I have not checked it out yet, myself because for me, the activation center opens at 5 a.m. but I know some of you are in other countries and the time is different. I hope this helps you all.

The Microsoft tech on the forum said that there is a phone option. Actually, what he means is you can call a Microsoft Activation Center. For the USA it opens at 5:00 A.M. and is based in New York. I just wanted to share the post with you that I had made and the tech's reply as well as the link for you guys for the activation centers. Hopefully it will help you. Good luck to all. Az.
My post url:
Getting error code 0xc004c003 also after installing Windows 10 - Microsoft Community

Licensing Center List url:
Microsoft Volume Licensing - Activation Centers

 

my drama update:

After the laptop, I did the upgrade to Win10 for the desktop as well, the PC had Win 8.1 Pro 64 fully updated and signed with the same MS account, it was reserved for the Win 10 upgrade, and the reserved upgrade was ready to go, indeed this time I used the Windows Update instead of the Media Creation Tool.
I tried to replicate the same procedure I did with the laptop, so I changed the Computer name accordingly, for now I'm sticking with an easy scheme, es: ZORRO-LAPTOP and ZORRO-DESKTOP, just to have a bloody clue of what is happening in the MS account page.

My laptop is currently activated and I can see it enlisted on the devices list from the MS account page, it shows the Computer's name and the brand of the laptop, the OS version is there also; the Computer's Name is visible in black font color while the brand is a gray color.

The Upgrade to Win 10 went fine and the OS was activated, the device was added to the device's list in the MS account, es: ZORRO-DESKTOP Gigabyte; all seems fine then I did a clean install(format), I made a mistake to not disconnect the lan cable, so the installation used some upgrades before moving to the desktop.
I had created a local user during the installation and then switched to the MS account for the activation, the device's list in the MS account had 2 instances of ZORRO-DESKTOP Gigabyte after the clean install, and it didn't activate, 0xC004C003 error.
I removed the 2 device instances for ZORRO-DESKTOP and tried again with another clean install, this time without the lan cable, after switching to the MS account there was no sign of the ZORRO-DESKTOP on the account page, and still 0xC004C003 error.

I did a full reinstallation of Win 8 Pro 64, using he same schemas (ZORRO-DESKTOP), and I did all the updates up to Win 8.1 Pro, I was signed in the store of corse, and the apps were updates(One Note had a error but really....wtf). I did a checkdisk(GUI) of the system C: and a sfc /scannow, this time I made a disk backup stored on a secondary HDD. no cleanups or registry clean were made so I did an extremely 'raw' or 'linear' upgrade to Win 10.

Happened that the OS was upgraded, activated, but ...., in the MS account page i had the instance of the laptop and a new one called PC , which means as I esplained before, no Computer Name, no Brand .... just a bloody PC, and no version of the OS!!!!!! ooh dear this is a quest.

In the search of the Holy Grail, I made some PC reboot to see if the account get syncronized somehow, something changed, there was a next link right next the OS version in the system window(where you see PC specs and activation status), this link will ask you to change the activation code(I didn't continue), rebooting the PC made that link go away; anyway nothing changed on the device list in the MS account page.

I removed the device from the MS account and it asked me to make a Factory Reset to assign the device again to the account; so I did a Factory Reset maintaining the user stuff, I'm not reselling the PC, I'm just resetting it; the process completed and the system resetted correctly and activated as well ...cool; In the MS account I had the laptop device(correct) and 2 instances of the PC, ZORRO-DESKTOP Gigabyte (Windows 10 Pro and version) and again PC .....wtf! and the next link was back into the system window.(reboot didn't fix it this time)

That was still the upgrade version from the Win 8.1 Pro process, I didn't made any clean install, I want to be sure before moving on; I did a checkdisk(GUI), I did a sfc /scannow which reported some damaged files it couldn't repair, rechecked the updates from the Windows Update and the Store as well, then again sfc /scannow still giving some warnings on damaged files it couldn't repair.
I Disconnect the MS account in favour of the local user the I did a reboot, after the boot up completed and logged into the desktop I checked the system window and the next link went away(some updates went on in the background), Nothing changed on the MS account.
I switched back to the MS account on the PC, and the next link back in, a reboot removed the thing this time; nothing changed on the MS account.

I did a winver this time ....and, the version is showed up correctly but on the bottom of the windows it say the licence is in use for: microsoft microsoft, yes 2 times microsoft; so I did a check on the laptop and there i got the local user name; this reflect somehow what is happening on the MS account page for the device list.

Now what that microsoft in winver means? means the OS is granted to a MS accounts? so why the laptop has the local user name i made? the license maybe means its not granted to me at all?

the laptop has the grant to the local user, and I did 2 clean installs(format) and it was activated without problems(well actually there is a twin story on the laptop some posts early in this thread).
I didn't perform a clean install(format) on the PC yet, today its too bloody hot I need to wait for a clean install.

If you have the 0xC004C003 error please check your winver and your MS account devices to see if you have the same issue.

edit: also if you re activated check the winver on your PC and compare with your MSA(Microsoft Account) this could help some folks to understand if their system went upgraded correctly.

Looks like its recommended to wait some time after the upgrade to Win 10 before adventuring in a clean install, run all the upgrades you can, do a sfc /scannow could help, check your winver and your MSA, reboot sometime, just play with it; the hardware ID that Microsoft could store to align the hardware to the licence could take some time.

 

I had problems after the upgrade on the 30th. So I downloaded the iso on to a usb stick. Then this morning I installed 10 from the usb. I selected the correct version and it then installed ok, skipping any input for code. When it was fully installed and set up I checked that it was activated. It say it is and there was no activation button. This was a clean install.

 

Hi, again everyone. I had posted a response to another person a bit ago about the error code: 0xc004c003. I just got off the phone with Microsoft Volume Licensing Activation Center.

What the tech said about this error is that the servers are really overloaded with people downloading the upgrade and activating their Windows 10. I asked about the Windows 7 key being used with 10 during activation. He said that when people upgraded to 10 they got a whole new key, which is why you are seeing the last 5 digits/letters when you try to activate it, and it's different from your other product key.

He said that over the next several weeks, people will be able to activate their Windows 10, once it is *unblocked* as it is being done in phases for people. So, just keep checking to see if you can activate it.

It was helpful information...a lot better than some of the other techs I spoke with who just..disappeared on me.