0x80072020 error when trying to access the Active Directory using LDAP within ASP

Hi Experts,

I'm creating a script that queries the AD to find all our employees and f.e. their phonenumbers. The script works fine locally on my Win2000 machine. When another user tries the open the page he/she gets the 0x80072020 error on the line 7 (marked in the code). In the IIS properties IWA has been selected as authentication method.

[code]
Set conn = CreateObject("ADODB.Connection")
Set rs = CreateObject("ADODB.Recordset")

Set oRoot = GetObject("LDAP://rootDSE")
sDomain = oRoot.Get("defaultNamingContext")
Set oDomain = GetObject("LDAP://" & sDomain) <------ the line that results in an error

sBase = "<" & oDomain.ADsPath & ">"
sFilter = "(&(objectCategory=person)(objectClass=user)(description=*)(!description=Mailbox)(sn=*)(!Description=Built*))"
sAttribs = "adsPath"
sDepth = "subTree"

sQuery = sBase & ";" & sFilter & ";" & sAttribs & ";" & sDepth

conn.Provider = "ADsDSOObject"
                   
conn.Open "Data Source=Active Directory Provider"
 
rs.Open conn.Execute(sQuery)

If Not rs.EOF Then
   'do stuff
End If

rs.Close

Set rs = Nothing
Set conn = Nothing
Set oRoot = Nothing
Set oDomain = Nothing
[/code]
Using google I found out that this most likely has something to do with access-rights within the Active Directory, but I can't seem to find the correct answer how to solve this. Could someone explain to me what rights (policy?) need to be added to all the users so that they can query our AD using the ASP page?

I've posted this question in the OS/W2k3 selection, because I suspect the solution lies here and not within the ASP-page I've created.