Self-answer
Two problems - my ext dir pointer in the ini file had a semi-colon instead of a colon after the c ie c;\php instead of c:\php
But also the system was not finding the php file on c anyway because I did not read the manual carefully enough. As well as adding C:\php to the path you also have to create a new variable - a phprc variable in the "environment variables" section of Win XP.
So this is resolved may I tell the mediators