Ok, i think we might be going off the beaten track slightly here.
Can you go into the following:
C:\Windows\System32\LogFiles\W3SVC1
Open up your latest log file, chances are you wont see the following line:
2009-04-16 23:06:44 W3SVC1 10.64.118.137 POST /reporting/admin/upload.php - 80 - 19.103.103.250 libwww-perl/5.803 200 0 0
Last 2 questions :)
Are you able to go to the following URL:
http://ReportingServerIP/reporting/admin/upload.php
You should be presented with a Blank Page. If not and you are challenged to supply Windows Credentials it is then your IIS config and more specifically your IUSR_<ServerName>
Can you paste up the last lines of your latest W3SVC1 Log file so we can see whats going on.
Thanks,