problem in retrieving image from a Database using WCF service

[cool_zephyr]

hey there, I'm writing a program where I have to store and retrive student information(e.g. name,address,photo..) in the database. I've written the code to interact with the database in a WCF service..The problem is I'm able to get the image from the database if I directly write the code to interact with the database in the Windows Forms Application..but when I try to get the image through the WCF service there's some sort of error saying "The underlying connection was closed: The connection was closed unexpectedly."
I don't understand where I'm going wrong..Could anyone please tell me why am I getting this error???
The function in the WCF service that retrieves the image is given below

public System.Drawing.Image GetImageByRecID(int iRecID)
        {
            System.Drawing.Image imgResult = null;
            try
            {
                OpenConnection();
                string sqlQuery = @"SELECT Stud_photo FROM Student_PhotoTable WHERE (STUD_ID=" + iRecID.ToString() + ")";
                sqlCmd.CommandText = sqlQuery;

                SqlDataReader dtreader = sqlCmd.ExecuteReader();                

                if (dtreader.HasRows)
                {
                    dtreader.Read();
                    byte[] imageBytes = (byte[])dtreader["Stud_photo"];

                    imgResult = this.ByteArrayToImage(imageBytes);
                }

                CloseConnection();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                CloseConnection();
            }
            return imgResult;
        }

...the OpenConnection() and CloseConnection() are functions to open and close the database connection respectively..and the byteArrayToImage() function just converts the byteArray into the corresponding image

[cool_zephyr]

I got it right..just return the byte array from the WCF service and then change the byte array into the image in the client application