Sometime Windows Update on Windows clients wont sycronize with your WSUS server, or wont download an update that recently been pushed out.
If that happeneds try this:
net stop wuauserv
REG DELETE “HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdateAuto Update” /v LastWaitTimeout /f
REG DELETE “HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdateAuto Update” /v DetectionStartTime /f
REG DELETE “HKLMSoftwareMicrosoftWindowsCurrentVersionWindowsUpdateAuto Update” /v NextDetectionTime /f
net start
wuauserv
wuauclt /detectnow
