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I have just built my own PC and I bought Windows 11 Pro (I am using this for home not a business). After installing and configuring the OS I cannot personalise Windows as it tells me that it needs to be activated. I entered the 25 digit key as part of the installation process and no errors were reported. I have a Microsoft Account with a PIN set up. When I first started the PC it would not boot and I had to remove and replace the graphics card, memory and SSD in order to identify the issue - a badly seated memory card.
I have not made any changes to the system since I built other than described above but I keep getting error code 0xC004C008 when I try to activate Windows.
I have been around and around the support activation help but nothing has worked and I just keep going round in circles.
Not sure if it is related to this issue but I also cannot connect Outlook to my email address. I get a "You cant sign in here with a personal account" but I only have a personal count and I am using Office 365 family subscription. I have been using this for 10 years or so without problems previously.
I have already tried everything suggested by the AI nothing has worked.
Hello
Where did you get the license? Did you purchase from Microsoft, or third party?
Can you please type cmd in the search on the taskbar and hit enter to launch command prompt, then run the following command:
slmgr /dlv
Then share a screenshot please. Thanks!
Also I have managed to get the issue with Outlook fixed - I had to setup the pop3 and imap info manually
Glad the outlook issue is sorted.
Regarding your license, did it work the first time, and then it wouldn't work after you made some hardware change?
If that's the case, try this first:
Please type cmd in the search on the taskbar. Don't press enter key yet. Instead, choose "run as administrator" to launch Command Prompt.
Run these commands one a time:
slmgr /upk
slmgr /cpky
Restart the computer, then go to Settings > System > Activation > Change product key. Input the key and see if it takes. If the last activation was less than 72 hours ago, you might need to wait a bit.
I got it from Amazon I think
Key from third party can be also problematic.. Microsoft cannot guarantee that it will always work. Try the above first.. hope for the best.
It worked the first as far as I am aware - I had no warnings or errors reported during the installation process. I did not make a hardware change per se just unplugged and re-plugged in the graphics card, memory and ssds but they were the same ones as originally used.
Unplugging and re-plugging would trigger a hardware "change" and license ask. This is normal.
I ran the commands as you asked and tried to activate windows after waiting for a couple of days as suggested but I still see the same error code 0xC004C008.
Is there anything else we can try or do I just need to buy a new license from the store? Unfortunately I do not have a record of where I bought Windows from. It was advertised as the retail version for £200+ but in the license it says it is OEM I believe.
If I do get a new license is it guaranteed to work with the installed Windows? Do I need to remove Windows and re-install fresh?
Colin, try to run the command:
slui 4
Then see if you can activate by phone.
If you want Microsoft support to help manualy, they would want to see proof of purchase.
If you et a new license you should be able to activate it.