80072020 Error in ASP LDAP Query

Hi,
I've this ASP code for query in LDAP. It works fine as vbscript, but in IIS
6.0 doesn't work with error 80072020 on line ... GetObject("LDAP://" &
strDomainDN)...
In IIS I've only checked "Integrated Windows Authentication"...
IIS Server in a standalone server 2003 joined to the smmi.it domain
Thanks a lot in advance!

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Function UsrLDAPinfo(userlogin,varuser)
Dim objRootDSE
Dim objConnection
Dim strDomainDN
set objRootDSE = GetObject("LDAP://smmi.it/RootDSE")
Set objConnection = CreateObject("ADODB.Connection")
objConnection.Provider = "ADsDSOObject"
objConnection.Open "Data Source=Active Directory
Provider;Provider=ADsDSOObject"
strDomainDN = objRootDSE.Get("defaultNamingContext")
Set oDomain = GetObject("LDAP://" & strDomainDN)
sBase = "<" & oDomain.ADsPath & ">"
sFilter = "(&(objectCategory=person)(objectClass=user)(name=" & userlogin &
"))"
sAttribs = "adspath"
sDepth = "subTree"
sQuery = sBase & ";" & sFilter & ";" & sAttribs & ";" & sDepth
Set rs = objConnection.Execute(sQuery)
Set user = GetObject(rs("adsPath"))
if Ucase(varuser)=Ucase("cn") then
UsrLDAPinfo=user.cn
elseif (varuser)=Ucase("firstname") then
UsrLDAPinfo=user.Firstname
elseif Ucase(varuser)=Ucase("lastname") then
UsrLDAPinfo=user.lastname
elseif Ucase(varuser)=Ucase("telephonenumber") then
UsrLDAPinfo=user.telephonenumber
elseif Ucase(varuser)=Ucase("displayname") then
UsrLDAPinfo=user.displayname
elseif Ucase(varuser)=Ucase("EmailAddress") then
UsrLDAPinfo=user.EmailAddress
elseif Ucase(varuser)=Ucase("description") then
UsrLDAPinfo=user.description
end if
rs.Close
objConnection.Close
End Function
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