How To Find Mail/Mailbox-Enabled Users in the Active Directory

(&(objectClass=user)(mail=*))

Sub Main()
'the purpose of this sample is to demonstrate how to query for
'mail/mailbox enabled User objects
'

Private Sub Command1_Click()
Dim oRootDSE As IADs
Dim objUser As IADsUser
Dim oConnection As New ADODB.Connection
Dim oCommand As New ADODB.Command
Dim RS As ADODB.Recordset
Dim strQuery As String, newattrib As String
Dim varDomainNC As Variant


On Error Resume Next
' Get the Configuration Naming Context
Set oRootDSE = GetObject("LDAP://RootDSE")
varDomainNC = oRootDSE.Get("defaultNamingContext")
' Open the Connection
oConnection.Provider = "ADsDSOObject"
oConnection.Open "ADs Provider"
'Build a query to find all mail enabled Users that do not have
'extensionattribute2 set
strQuery = "<LDAP://" & varDomainNC & -
 ">;(&(objectClass=user)(mail=*));adspath,cn;subtree"
oCommand.ActiveConnection = oConnection
oCommand.CommandText = strQuery
Set RS = oCommand.Execute
If RS.RecordCount = 0 Then
    Debug.Print "No mailbox enabled User found to not have extension attribute 2 set"
Else
    While Not RS.EOF
        Set objUser = GetObject(RS.Fields("adspath"))
        Debug.Print objUser.cn, " does not have extension attribe2 set"
      RS.MoveNext
    Wend
End If
Set oRootDSE = Nothing
Set objUser = Nothing
RS.Close
set RS = Nothing
End Sub
				

= "<LDAP://" & varDomainNC & -
 ">;(&(objectClass=user)(mail=*)(!(extensionAttribute2=*)));adspath,cn;subtree"