PHP4 Installaion problem

Hi please help me.... Right i was running a trial version of deerfiled website pro 3.1 and running php4 with no problems... now that the trial has expired i removed it and installed oreallys website pro 3.0 retail which i had previusely... after installing the new web site software, i installed php4, and editind the php.ini, setup mapping etc, and followed the install.txt perfectly... now ever time i run a script my browser (Internet explorer 6.0 on xp) says "No input file specified." i ran php.exe -i and i get the html to say it running fine... so what could be wrong??? Thank you...