In the machine image, copy zisReboot.exe into your winnt\system32 (or equivalent) directory. Make the following registry change - in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon : add ',zisReboot.exe' (without the quotes) to the end of the System value (so it will probably look like 'lsass.exe,ziswin.exe,zisReboot.exe' on Windows NT). zisReboot must be the last value, otherwise nasty things may happen.
Next time the machine is rebooted, the zisReboot program will wait 5 minutes, and if ziswin.exe is still running at that time (which suggests the 'Please restart your computer now' prompt is there), it will automatically reboot the machine. It will then remove itself, so this change should be made immediately before creating the image.
* Note that the reboot seems to fail if you are at a username/password prompt box - so if you have the 'Press Ctrl+Alt+Delete' window disabled, this will probably not work. A fix for this would be welcome...
Source here.
Simon Pollard, simonweb@ruffles.org.uk 30/06/2003