Web Forms :: Server 2008 R2 - IIS7 And Running .exe Files

I'm using ASP.net 3.5 to run a .exe with Process.Start(). It works fine if I use the host that's built-in to VS2008, WinServer 2003 but if I use IIS7 it no longer runs. I am using the following code.

Process proc =
new
Process();
proc.StartInfo = psi;
proc.StartInfo.FileName = "cmd.exe";
proc.StartInfo.Arguments = args;
proc.Start();