Microsoft Project Server 2007 Authentication Problem

i configure my project professional 2003 to connect with PWA 2007 and then click test connection:
The following file(s) have been blocked by the administrator: /PWA/isapi/pjdbcomm.dll

i did it this:
http://www.projectservertips.com/PJDBComm.dll_Blocked.htm

but in the IIS doesnt exist ISAPI folder because this solution is ti project server 2003 and i’ve project server 2007