Web service open an external app in server 2003

What permission set do I need?

[korkus2000]

On win2k server I have no problem opening an external app. Since server 2003 is fully locked down from the beginning I can't find the permissions I need. I can create my own application pool that runs as local system to achieve this but it is a real security risk. Does anyone know where and what permissions are needed?

I did imporsonation but it seems only administrators and system can do this. I created my own user with all rights available and it still would not allow it. Any help would be appreciated.

[korkus2000]

I got it figured. If you run into a problem like this I used filemon and regmon to check calls to the registry and to the file system. 2003 uses the network service user instead of the aspnet user in some instances. I am guessing for ntfs permissions. Switched to network service permission user and it works on 2003 now.