For a significant hardware change like a motherboard replacement, Windows 11 may no longer activate because the digital license is associated with the device hardware. If the old device was not linked to a Microsoft account, the Activation troubleshooter is less likely to help.
Supported options are:
- Check the installed edition and activation page
Go to Start > Settings > System > Activation. Confirm the installed edition matches the license entitlement, such as Windows 11 Home or Windows 11 Pro. If the edition does not match, Windows will not activate. - Try reactivation with the retail product key
In Start > Settings > System > Activation > Change product key, enter the 25-character retail product key. This is the supported path after a hardware change if Windows was not reinstalled, and the same key can also be entered during installation if Windows is reinstalled. - If the old license was linked to a Microsoft account, use the Activation troubleshooter
Go to Start > Settings > System > Troubleshoot. This requires an internet connection and administrator access, and the option appears only while Windows is not activated. For hardware changes, the supported flow is to choose I changed hardware on this device recently, sign in with the Microsoft account linked to the digital license, select the old device, check This is the device I’m using right now, and then select Activate. - If Troubleshoot does not work and there is no linked device, contact Microsoft support
If the troubleshooter cannot fix the issue, the documented next step is to contact customer support. A Microsoft Q&A answer also points to using the Get Help app in Windows, searching for billing, then selecting Contact Support to reach chat with an agent in the browser. - If the motherboard was replaced by the original OEM, automatic reactivation may occur
If it does not, and a COA card was provided with a 25-character key, enter that key through Settings > System > Activation > Change product key.
Also verify that Windows activation has internet access before retrying.
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