SYSPREP the computer.
1. Remove the computer from domain
2. Open a CMD window.
3. CD \sysprep
4. ipconfig /release (then unplug from network)
5. sysprep forceshutdown quiet mini activated (this starts the sysprep gui)
6. close the CMD window
7. use the RESEAL button on the sysprep gui to initiate.
8. Once the computer has shutdown the system is ready to have the image saved. Be sure when restarting to have the network boot CD or disk in the drive.