After having installed new update(s), Windows 7 would by default reboot your computer without even bothering to ask you if you are fine with losing your unsaved data or interrupting on-going calculations. To avoid this, feed the following into the registry (create a *.reg-file with this content and double-click it):
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU] "NoAutoRebootWithLoggedOnUsers"=dword:00000001
This will grant you a repeated choice between 10 minutes, 1 hour and 4 hours of postponed reboot. (Shouldn’t this be default behavior?)
