Must be unzipped to C:\ (so it becomes C:\SCRIPTS).
Import the scheduled take by going into Task Scheduler, clicking Import Task, navigating to C:\SCRIPTS and selecting WSUS_Cleanup_v2.xml. I recommend calling the task WSUS_Cleanup_v2
Warning : If run on a server which hasn’t been tided for a while it may take MANY HOURS (I’ve seen it take 17hrs!) and may require multiply times. I’ve set up a schedule before and kept an eye on it over a period of days, after about three days it starts to complete successfully and quickly. I seems to take a few goes for things to settle down.