Run the runsysprep as an administrator, the sysprep generalizing tool popup launches and seems to work but it stops after a while without rebooting the device to boot on PXE, no matter what. Everytime you'll reboot the device after that it will ask you if you want to manually generalize it.
This is due to some window component that is failing. You will probably find interesting logs in the logs given in "D-" and in %SystemDrive%\Windows\DtcInstall.log about this or in the Panther logs.
I've tried to fix this by the past but never managed to and i finally reinstalled the entire system.
You might want to try this workaround depending on what you find there though: How to Uninstall and Reinstall the MS DTC.
- This article applies to FPAC 11.6 (and probably to all other versions too).
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