When you use the System Preparation (Sysprep) tool on a Windows Vista-based computer, you may receive the following error message:

A fatal error occurred while trying to sysprep the machine.

Additionally, an error message that resembles the following is logged in the Setuperr.log file:

Time, Error [0x0f0073] SYSPRP RunExternalDlls:Not running DLLs; either the machine is in an invalid state or we couldn't update the recorded state, dwRet = 31


This error message is designed to prevent the deployment of a corrupted image. When you run the Sysprep tool, its progress is tracked through each of the phases of Sysprep. Sysprep does not have a way to roll back when it experiences errors.


When you experience this error, you must re-create the image. You cannot correct the problem with the image. When the Sysprep tool runs, it clears the %windir%\system32\sysprep\panther\setupact.log file. Therefore, it is not possible to see what failed the last time that the Sysprep tool was run. To see what failed when you last ran the Sysprep tool, you must have a copy of the %windir%\system32\sysprep\panther\setupact.log file that existed before you ran Sysprep.

Note Before you create a new image or run the Sysprep tool again, we recommend that you save the contents of the following folders:

  • %Windir%\Panther

  • %Windir%\System32\Sysprep\Panther

Note Make sure that you save the contents of all the subfolders of these two folders.

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