To restore the number of Extended Security Update (ESU) licenses for Windows 10, you will need to follow the process outlined by Microsoft for managing your ESU licenses. Unfortunately, the context does not provide specific instructions on how to return or reallocate ESU licenses once they have been applied to a device. Typically, ESU licenses are tied to the device they are activated on, and returning them may not be straightforward.
You may want to contact Microsoft support or your volume licensing representative for assistance with returning or reallocating your ESU license from the unused PC. They will provide you with the necessary steps based on your specific situation.
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