DistListItem.MemberCount Property (Outlook)
Returns a Long indicating the number of members in a distribution list. Read-only.
The value returned represents all members of the distribution list, including member distribution lists. Each member distribution list is counted as a single member. That is, MemberCount is not an aggregate sum of the recipients in the distribution list plus recipients in member distribution lists. For example, if a distribution list contains 10 recipients plus one distribution list containing 15 recipients, MemberCount returns 11.
This Microsoft Visual Basic for Applications example steps through the default Contacts folder, and if it finds a distribution list with more than 20 members it displays the item.
Sub CheckDLs() Dim myOlFolder As Outlook.Folder Dim myOlItems As Outlook.Items Dim myOlDistList As Outlook.DistListItem Dim x as Integer Set myOlFolder = Application.GetNamespace("MAPI").GetDefaultFolder(olFolderContacts) Set myOlItems = myOlFolder.Items For x = 1 To myOlItems.Count If TypeName(myOlItems.Item(x)) = "DistListItem" Then Set myOlDistList = myOlItems.Item(x) If myOlDistList.MemberCount > 20 Then MsgBox myOlDistList.DLName & " has more than 20 members." myOlDistList.Display End If End If Next x End Sub