If you think any other questions should be included in this FAQ, please mention it below and I'll see what I can do.
1. Can I activate W10 using my W8 or W7 license key?
No. W10 can't be activated with anything but a W10 license key.
A W10 key is acquired by either:
a) purchasing a retail copy of W10, or by
b) doing an in-place upgrad of your genuine and activated W8.x or W7.1 installation (while being connected to the internet!)
Option (b) does the following:
a) creates a new W10 license key based on your existing/active/installed license key
b) stores the W10 license key in the cloud
b) creates a key that identifies the hardware your copy of W10 is running on and associates that with your new W10 license key
From here on out (for the machine you installed W10 onto) W10 will no longer require you to provide any key for activation purposes.
After having done the above, you can also clean-install W10 from any source (USB thumb drive, DVD, Media Creation Tool) without requiring a license key. See (2) below for more information.
2. I did a W10 clean-install from bootable media (ISO, USB Drive, DVD, etc). Now I can't activate W10. What's up?
Prior to doing a clean install, you must have done an in-place upgrade of your W8.x or W7 installation at least once. Whether that occurred before the 29th with an insiders preview install or afterwards doesn't matter. It just must have occurred. Failing that, MS will have no online record of your upgraded W10 license key nor of the hardware it was associated with.
See (1) above for more information.
After having done an in-place upgrade, you can then clean-install W10 and skip all the prompts where the setup process asks you for a W10 key. At the end of the setup process, once you've gone online, Windows will notice your valid W10 license that was previously stored in the cloud and use it to activate W10.
3. I'm not getting a prompt to upgrade my W8.x or W7 installation. Why not? What should I do?
The W10 rollout is staggered. Those who reserved W10 early will be able to upgrade sooner. You might not be scheduled for the update quite yet, but you can force an update.
This WCentral article explains one of your options, and this one explains more. The issue is also being discussed in this thread.
Last but not least, you can also download the media creation tool, run it, and then choose the "Upgrade this PC now" option. This also does an in-place upgrade, not a clean install.
4. Where can I download the official installation media to do a clean install?
Windows 10 media creation tool
Windows 8.1 media creation tool
Windows 7.1 ISO download
5. "Windows not activated" after clean install. Attempting activation results in error code: 0xC004C003. What now?
You're likely a victim of some of MS' activation servers being overloaded.
MS has sent out e-mails stating that waiting for a day or two should automatically resolve the issue. This has also been confirmed by MS support staff, and many of our members in the forum.
1. Can I activate W10 using my W8 or W7 license key?
No. W10 can't be activated with anything but a W10 license key.
A W10 key is acquired by either:
a) purchasing a retail copy of W10, or by
b) doing an in-place upgrad of your genuine and activated W8.x or W7.1 installation (while being connected to the internet!)
Option (b) does the following:
a) creates a new W10 license key based on your existing/active/installed license key
b) stores the W10 license key in the cloud
b) creates a key that identifies the hardware your copy of W10 is running on and associates that with your new W10 license key
From here on out (for the machine you installed W10 onto) W10 will no longer require you to provide any key for activation purposes.
After having done the above, you can also clean-install W10 from any source (USB thumb drive, DVD, Media Creation Tool) without requiring a license key. See (2) below for more information.
2. I did a W10 clean-install from bootable media (ISO, USB Drive, DVD, etc). Now I can't activate W10. What's up?
Prior to doing a clean install, you must have done an in-place upgrade of your W8.x or W7 installation at least once. Whether that occurred before the 29th with an insiders preview install or afterwards doesn't matter. It just must have occurred. Failing that, MS will have no online record of your upgraded W10 license key nor of the hardware it was associated with.
See (1) above for more information.
After having done an in-place upgrade, you can then clean-install W10 and skip all the prompts where the setup process asks you for a W10 key. At the end of the setup process, once you've gone online, Windows will notice your valid W10 license that was previously stored in the cloud and use it to activate W10.
3. I'm not getting a prompt to upgrade my W8.x or W7 installation. Why not? What should I do?
The W10 rollout is staggered. Those who reserved W10 early will be able to upgrade sooner. You might not be scheduled for the update quite yet, but you can force an update.
This WCentral article explains one of your options, and this one explains more. The issue is also being discussed in this thread.
Last but not least, you can also download the media creation tool, run it, and then choose the "Upgrade this PC now" option. This also does an in-place upgrade, not a clean install.
4. Where can I download the official installation media to do a clean install?
Windows 10 media creation tool
Windows 8.1 media creation tool
Windows 7.1 ISO download
5. "Windows not activated" after clean install. Attempting activation results in error code: 0xC004C003. What now?
You're likely a victim of some of MS' activation servers being overloaded.
MS has sent out e-mails stating that waiting for a day or two should automatically resolve the issue. This has also been confirmed by MS support staff, and many of our members in the forum.
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