by Ken Task.
Not a Windows person (obviously), but the idea, however, is the same ... it's reporting: not readable-check permissions.
This might help:
http://technet.microsoft.com/en-us/library/cc754009%28v=ws.10%29.aspx
But, am almost certain, those that do run Windows will ask for more information ... IIS version, Server 200x, etc.. Or did you install the Windows package from downloads.moodle.org ... which are NOT server versions.
'spirit of sharing', Ken