Configuration :: Image Display / Move It To Live Server, It comes Up With An Empty Image Box?

I have a routine to display an image on an aspx page. The url for the image uses imagerender.aspx . This is simply an empty page with code behind:

myClass mysub = new Myclass(); // create class
Stream strm = mysub.DisplayImage(UserID); // call method to load bytes from db
byte[] buffer = new byte[2048];
int byteSeq = strm.Read(buffer, 0, 2048);
while (byteSeq > 0)
{
Context.Response.OutputStream.Write(buffer, 0, byteSeq);
byteSeq = strm.Read(buffer, 0, 2048);
}

Ok, this work fine when testing on my local machine, but when I move it to the live server, it comes up with an empty image box!

It looks like there must be a problem with security, maybe with ISS.

Does anyone know what changes I can make to fix this problem or what setting to change in IIS 7?