vereato says:
            
            Str = "SELECT User_Name FROM tbl_users WHERE User_Name=@User_Name, _Picture=@_Picture "
            Cmd = New MySqlCommand(Str, Conn)
            Cmd.Parameters.AddWithValue("@User_Name", Session("User_Name").ToString())
           
            Cmd.Parameters.AddWithValue("_Picture", MySqlDbType.Blob).ToString()
            
Replace above with below.
Str = "SELECT User_Name FROM tbl_users WHERE User_Name=@User_Name"
Cmd = New MySqlCommand(Str, Conn)
Cmd.Parameters.AddWithValue("@User_Name", Session("User_Name").ToString())