I found this this morning when we has a powercut. I have a UPS so I wasn't affected straight away. I usually close programs individually but in this case I just went for Start => Turn Off Computer. All other applicatons closed as expected, but WSWIN just kept running and neutralised the shutdown request. I could not do a controlled shutdown without first stopping WSWIN manually.
I'd previously noticed that WSWIN resisted automatic closure of Windows by a utility that I use called Timed Shutdown[1].
It seems unusual for a Windows program to resist shutdown like that. What would happen if my UPS was trying to close Windows programatically because the battery was running out? Maybe there is some option that I've missed?
[1] I've since noticed that WSWIN has its own timed shutdown facilities, which seem very comprehensive, but I happen to like the utility I already use...