Came across this blog posting from a Microsoft employee <https://devblogs.microsoft.com/oldnewthing/20151211-00/?p=92501> from a few years ago, which manages to address, yet avoid, the issue of Windows needing reboots to properly apply updates. Note the question: “Hasn’t the problem of updates being partially installed until the next reboot already been solved by changes in Windows?” The answer begins: This is, to a large extent, true. Modern versions of Windows use Component-Based Servicing (CBS). This technology makes sure that new Windows components, and new versions of existing components, are installed atomically. In other words, if it is possible to install or update a component without a reboot, CBS does so. If it is not possible (because one or more files are in use, or because the component requires more complicated setup), then the entire installation of the component is automatically suspended until the next reboot. However, it then continues to point out that many subsystems do not use this “CBS” technology, notable ones being drivers and Microsoft Office. And also remember, it doesn’t seem possible to replace components being, by running services. Can’t you fix this by stopping and restarting the affected services? On Linux, this is the obvious solution. Yet it never even occurs to this Microsoft engineer: Second, even setting the “Does the update do the right thing before the reboot?” problem aside, CBS itself creates another problem in this scenario. Since many Windows updates wind up getting their processing delayed until the reboot, that reboot itself can take longer (since all those pending operations then get performed). And in an environment where The Machine Simply Must Work, this means that the consequences of an accidental/unplanned reboot can be even worse.