I just built a new PC with XP Pro sp3. Everything is up to date. MSI H61M P23 board, i3 2100 CPU, Corsair XMS3 4GB PC10666 DDR3 RAM, Seagate 1TB LP SATA HDD. We schedule every PC to reboot overnight with our startup script. The command we use is "AT 04:15 SHUTDOWN -R -F -C". This has worked fine for all other PCs. This new PC seems to hang at the shutdown. Every morning it is stuck on the light blue screen, and there is no message box. The mouse works, but nothing else does, such as ctrl+alt+del. Someone has to hold the power button in and shutdown and restart the PC. I can shut it down and restart it manually and with the command with no problems during the day. I see the command to shutdown in the event viewer at 4:15, and then nothing until the manual reboot,then the usual service starting events. Anybody have any ideas?