Phew, it took me three goes to get that posted! After moving to the new Root Server I was having problems with some of the scripts that automatically create files somewhere in the document root.
To get this working I just decided to run Apache under the same user as the owner of the document root. This then caused the problem that all the session variables were not being saved! Quick chown to the new user on the temp directory used to save the session files sorted that.
I'm a web developer based in the East Midlands, UK and if I keep up the current rate, I might have developed 3 million sites by the time I retire