Microsoft tracks every Windows PC through a secret key

Microsoft embeds a persistent Global Device Identifier (GDID) into every Windows installation to uniquely track specific OS instances. This 64-bit identifier is generated by Microsoft servers and stored locally within the registry under the LID entry in the IdentityCRL key. While the company maintains that the GDID is for internal use, it is deeply integrated into various system features, including Windows activation, app licensing, and diagnostic data collection. Source

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