Windows Update runs occasionally on my machine, but it steals focus when it pops up to remind me to reboot.
Trouble is, this can mean that while writing something, you could force an immediate reboot.
Is there a way to prevent this thing from stealing focus? It seems to me that no modal dialog box should ever steal focus without a delay on accepting input. Especially if that input can restart the machine when you hit 'n'.

This is similar to this question: Preventing applications from stealing focus But I don't think it's a duplicate. We're not talking about "dubious software developers", or third party apps.
sc stop wuauserv– and31415 Aug 09 '14 at 13:42wuauclt.exe. Killing the process is futile: it will be respawn automatically. What you can do, however, is to prevent it from running altogether. The dialog will be gone, and it won't steal the focus anymore. You will also lose Windows Update notifications such as: New updates are available, Downloading and installing updates, Windows installed new updates. Would that be a viable solution for you? – and31415 Aug 10 '14 at 13:23