There have been many arguments about Microsoft Windows as a stable enough OS for enterprise VoIP deployments. The fact of the matter is most high-end enterprise class phone systems use Microsoft Windows systems in one way or another; from Cisco to Mitel.
Then we have SMB class of VoIP phone system that run day in and day out on Microsoft Windows platform. In a sense, these systems are actually more demanding on the base OS as instead of breaking up different aspects of a VoIP system into different hardware platforms, everything is run on an off-the-shelf PC.
The proliferation of Windows based VoIP systems shows that Windows can be used for mission critical systems, it may require reboots after updates but at least it’s consistent and comes with support from the developer.
Don’t get me wrong, the Asterisk on top of Linux is a venerable setup but setup and device compatibility can be a chore.

