Maintaining Windows support is a huge effort. Because Windows has not been widely adopted in the Open Source community and almost no contributions are coming from the broader community to support Windows, the team has focused their energy elsewhere, e.g., Exascale, reservations, Ubuntu, etc. (Also, the code base for Windows really needs to be refactored to be maintainable, and that is also a large effort.)
For all these reasons, we decided not to support Windows in OpenPBS.
I don’t know if this is an option for your organization,… because PBS Pro has many long-term support contracts and because Windows is more widely adopted in the commercial world, Altair offers Windows support with PBS Pro, which shares the same core technology as OpenPBS. Use the contact link at altair.com to get more information.
At some point in the future, after all the Windows code is refactored, and if there is more use of (and more contributors to) the Windows version in the Open Source world, perhaps we can bring it back.