What is Sysprep, and how to set up?

In a nutshell however, Sysprep configures a number of OS settings on the master image to ensure that every copy of the image is unique when deployed to a target system – in particular the System Security Identifier (SID). Were we to push an image out that had not been sysprep’d, the target computers would all share the same SID, which would present a security risk.

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