by Mauno Korpelainen.
Those paths in your screenshot and in this url request are different:
F:\inetpub\MOODLE2\theme\image.php VS F:\inetpub\MOODLE\Moodle2\theme\image.php
And http://localhost:80/moodle2/theme/image.php is not probably the same as http://stmichaelsrc.sbcschools.org.uk/moodle2/theme/image.php
Is there some kind of url rewrite rule / server cache enabled ?