As someone that manages the auto-update process of an application I have tried to mimic Google in the seamless updating process. The biggest problem is that Microsoft's policy is that you cannot overwrite an EXE or DLL if its in use. This is more than likely core to the OS and the reason Google require a restart. There was talk 3 years ago [1] about adding patching the Linux kernel for updates during run time [2], however if I recall it was rejected at the time due to the massive security threat it could have created. Imagine if a hacker got access to a function that allows you to rewrite any part of the kernel whilst its working. Effectively you could not be sure of anything any more. [1] http://www.l0t3k.org/biblio/kernel/english/runtime-kernel-kmem-patching.txt [2] http://lwn.net/Articles/311987/