Are you using Image control or PictureBox? You have posted the question with ASP.NET tag but I think picture box is used in winform applications and not in web applications or ASP.NET.
If you are using windows application, use the Image property instead of ImageLocation. Try the following process:
Create a Bitmap object from the image in your stream.
Then use this Bitmap object to set the Image property of your picture box.
Here are some more details:
http://msdn.microsoft.com/en-us/library/system.windows.forms.picturebox.image(v=vs.110).aspx[
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