The below is a very simple sysprep Unattend.xml for Windwos 7 x64.
By adding <SkipRearm>1</SkipRearm> to the unsttended.xmlsysprep you can sysprep as many times as you want.
Copy this file to C:\ and run sysprep.
<?xml version="1.0" encoding="utf-8"?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
<settings pass="generalize">
<component name="Microsoft-Windows-Security-SPP" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<SkipRearm>1</SkipRearm>
</component>
</settings>
</unattend>
