Interesting, has your issue been resolved? I’m having an issue that closely resembles your own. My working theory is that a run away process causes the worker process to recycle itself. Upon recycling itself something happens to the PHP namespace. A full reboot isn’t necessary for us. A simple iisreset from the command line resolves the issue. This seems like a non WordPress issue however I was hoping to find someone with some better WIMP experience than myself on here since I’ve not run in to this issue with other web applications.
