IUSR_MACHINE File System Permissions

I want to create a directory on a remote machine's share directory:

To do this, I use: Directory.CreateDirectory(\\\\remote-machine\\ShareDirectory\\NewFolder)

This works in a plain C# program, but not in an ASP.NET application. I think this is because the C# program uses the IUSR_MACHINE-NAME user.

I have both the share permissions and the security rights of that "ShareDirectory" to allow FULL CONTROL for the user group "Everyone" (which contains anyone!)

Why, then, does my ASP.NET app still not work!

Here is the error msg: "Access to the path '\\tsd-neptune-xp\Installers\TestFolder' is denied."
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