Access is denied to the network printers for ASP.NET App

Question

I have instaled asp.net application on a server. I want to display network printers in a dropdown and i use this codes to achive that goal:

 

Protected Overrides Sub LoadPrinters()
        Dim permison As New PrintingPermission(PrintingPermissionLevel.AllPrinting)

        If Not IsPostBack Then
            Dim strPrinter As String
            Dim li As ListItem
            dlPrinters.Items.Clear()
            dlPrinters.Items.Add(New ListItem("Select Printer", ""))

            For Each strPrinter In System.Drawing.Printing.PrinterSettings.InstalledPrinters
                dlPrinters.Items.Add(strPrinter)
            Next
        End If

Also i try this code:

 

Private Sub PrinterList()


    ' USING WMI. (Windows Management Instrumentation)
    Dim objMS As System.Management.ManagementScope = _
        New System.Management.ManagementScope(ManagementPath.DefaultPath)
    objMS.Connect()

    Dim objQuery As SelectQuery = New SelectQuery("SELECT * FROM Win32_Printer")
    Dim objMOS As ManagementObjectSearcher = New ManagementObjectSearcher(objMS, objQuery)
    Dim objMOC As System.Management.ManagementObjectCollection = objMOS.Get()

    dlPrinters.Items.Clear()
    dlPrinters.Items.Add(New ListItem("Select Printer", ""))

    For Each Printers As ManagementObject In objMOC
        If CBool(Printers("Local")) Then                        ' LOCAL PRINTERS.
            dlPrinters.Items.Add(Printers("Name"))
        End If
        If CBool(Printers("Network")) Then                      ' ALL NETWORK PRINTERS.
            dlPrinters.Items.Add(Printers("Name"))
        End If
    Next Printers
End Sub

In both scenarios i cannot see network printers in the dropdown list and if i use second code i can see error: Access is denied.

 

My application is using impersonate account with full permision to the network and printers. What else can make the problems?