when a Windows 7 system has been sysprepped three times -- KB929828. To overcome this, you will need to do the following:
1) Inside the Sysprep Unattend.xml file located at c:\windows\system32\sysprep, delete skiprearm=1from thesection. In order to edit the Unattend.xml file, you will need to slave the HDD onto a working machine in order to have access to a text editor for editing the file.
2) Under HKEY_LOCAL_MACHINE\SYSTEM\Setup\Status\SysprepStatus\, set GeneralizationState to 7
3) From an administrative command prompt, type the following
msdtc -uninstall
msdtc -install
4) Under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SoftwareProtectionPlatform\, change SkipRearm to 1
5) disconnect the ethernet cable
6) Rerun the sysprep
Fixing the "A fatal error occurred while trying to sysprep the machine" error
原文：http://549687.blog.51cto.com/539687/1886815