Although activation has been a requirement of Windows since the days of XP, the process isn't seamless. Activation issues can and do occur. Fortunately, there are ways you can troubleshoot Windows 10 activation problems.
Addressing the two main issues that can cause a Windows 10 activation error will fix the vast majority of problems.
The first of these issues is a lack of connectivity. Simply put, automatic Windows 10 activation does not work without internet access. Even if a computer is physically connected to a network that has internet connectivity, physical connectivity alone might not be enough. This is especially true for some of the older versions of Windows. For instance, you may encounter a Windows 10 activation error if the operating system's IP configuration does not reference a valid DNS server. If connectivity is not available or is not properly recognized, then you can get around the problem by using telephone-based activation.
Product keys can also cause a Windows activation error. This issue shouldn't usually be a problem for organizations that use volume licensing, but it can be problematic for those that do not. There is normally a limit to the number of times that product keys can be used. Once this limit has been exceeded, Windows will fail to activate. Even the multi-use keys that are available from sources such as the Microsoft Developer Network have built-in activation limits.
Although these are two of the more common causes of activation problems, they are far from the only ones. One issue that has received a lot of attention has to do with activations that fail due to hardware modifications. Suppose for instance that you have to replace a system's hard drive. In that situation, Windows would obviously have to be installed onto the new drive, and would also need to be activated. Windows 10 activation can fail if the product key has already been used. Similarly, replacing major components can also trigger the need for reactivation.
How to troubleshoot Windows 10 activation problems
Microsoft introduced an activation troubleshooting tool in the Windows 10 Anniversary Edition. To access this tool, log in to Windows 10 and go to Settings > Update & Security > Activation. Next, click on the Troubleshoot button at the bottom of the Activation screen.
Earlier versions of Windows, such as Windows 7 and Windows 8 were licensed using product keys. Although Windows 10 can accept a product key, Windows 10 actually uses digital licenses. These digital licenses have made it possible to perform in-place upgrades from some of the earlier Windows versions.
Microsoft strongly encourages customers to log in to Windows 10 using a Microsoft account. Upon doing so, Windows 10 automatically adds the device's digital license to the Microsoft account; the account becomes a license repository.
Now, suppose that you made a major hardware change to a device, and then you have trouble with the reactivation process. The first step to fix the problem is to go to Settings > Update & Security > Activation, and then click the Add an Account link. Now click the Troubleshoot button. When the troubleshooting window opens, indicate that there has been a recent hardware change, and then log in to your Microsoft account if prompted to do so.
At this point, you should see a list of the devices that are linked to your Microsoft account. Choose the device that you are currently using from the list of registered devices, and then click the Activate button. Windows should now activate.
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