Printers' name in Password protected server

[daka90]

Hi everyone, I'm new here
I looked hours on the net to find the answer to my prb...
I need to check all the printers of my faculty by sending a test page to everyone of them. And I want to do that with a little program in VB...
All the printers are in the same server.

I've found this piece of code :
It should get the names and put them in a list box (the following code) and them send the print request (any suggestion about that will be very welcome too )

        Dim moReturn As Management.ManagementObjectCollection
        Dim moSearch As Management.ManagementObjectSearcher
        Dim mo As Management.ManagementObject

        moSearch.Scope.Path.DefaultPath.Server() = "server_name"

        Try
            moSearch = New Management.ManagementObjectSearcher("Select * from Win32_Printer")
            moReturn = moSearch.Get
            For Each mo In moReturn
                ListBox1.Items.Add(mo("name"))
            Next
        Catch ex As Exception
            MsgBox(ex.Message)
        Finally
            moReturn = Nothing
            moSearch = Nothing
            mo = Nothing
        End Try

and when I'm running it I get " Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)) "
PS : I have the password of course, and I enter it in the terminal before executing the code.

If someone can halp me it will great.
Thanks a lot