Public Folders EntryID

Is it possible to know the EntryID of a Public Folders for contacts in Exchange without using the PickFolder method?

You can navigate down the folder structure to your destination public folder. Then get its .EntryID value.
This value does not ever change unless the folder is deleted and recreated.

Is the destination folder dynamic or will it be in the same location all the time?

Just in case, here is a demo to transversing the Public folders to a folder called "Development".

VB Code:

Option Explicit
'Add a reference to MS Outlook xx.0 Object Library
Private Sub Command1_Click()
    Dim oApp As Outlook.Application
    Dim oNS As Outlook.NameSpace
    Dim oPublicFolders As Outlook.MAPIFolder
    Dim oAllPublicFolders As Outlook.MAPIFolder
    Dim oFolder As Outlook.MAPIFolder
    Dim sEntryID As String
    Set oApp = New Outlook.Application
    Set oNS = oApp.GetNamespace("MAPI")
    Set oPublicFolders = oNS.Folders("Public Folders")
    Set oAllPublicFolders = oPublicFolders.Folders("All Public Folders")
    Set oFolder = oAllPublicFolders.Folders("Development")
    sEntryID = oFolder.EntryID
    Debug.Print sEntryID
    Set oFolder = Nothing
    Set oAllPublicFolders = Nothing
    Set oPublicFolders = Nothing
    Set oNS = Nothing
    Set oApp = Nothing
End Sub

Is it normal that this code is working on Outlook 2002 with Windows XP and not on Outlook 2002 with Windows 2000?

What error are you getting?

The operation failed. An object could not be found.

The error occurs on this line :

VB Code:

Set oPublicFolders = oNS.Folders("Public Folders")