Outlook monitor Subfolder and run Macro

Question

I'm having issues with getting some code to work. I have put it together from code I found and get an error stating the Sub or Function is not defined. I'm new to Outlook VBA and can't figure it out.

Option Explicit
Private objNS As Outlook.NameSpace
Private WithEvents objItems As Outlook.Items

Private Sub Application_Startup()
Dim objWatchFolder As Outlook.Folder
Set objNS = Application.GetNamespace("MAPI")
'Set the folder and items to watch:
'Set objWatchFolder = objNS.GetDefaultFolder(olFolderInbox)
'Set Inbox = Application.Session.GetDefaultFolder(olFolderInbox)
Set objWatchFolder = objNS.Inbox.Folders.Item("Zip Files")
Set objItems = objWatchFolder.Items
Set objWatchFolder = Nothing
End Sub

Private Sub objItems_ItemAdd(ByVal Item As Object)
Dim oFolder As Folder
Dim Date6months As Date
Dim ItemsOverMonths As Outlook.Items

Dim DateToCheck As String

Date6months = DateAdd("d", 0, Now())
Date6months = Format(Date6months, "mm/dd/yyyy")

Set Inbox = Application.Session.GetDefaultFolder(olFolderInbox)
Set oFolder = Inbox.Folders.Item("Zip Files")

DateToCheck = "[Received] <= """ & Date6months & """"

Set ItemsOverMonths = oFolder.Items.Restrict(DateToCheck)

For i = ItemsOverMonths.Count To 1 Step -1
ItemsOverMonths.Item(i).Delete
Next


Set ItemsOverMonths = Nothing
Set oFolder = Nothing

End Sub

If anyone can point me in the right direction that would be great.

Answer 1

See the Changes I made and compare it with yours

Option Explicit
Private WithEvents objItems As Outlook.Items

Private Sub Application_Startup()
    Dim objNS As Outlook.NameSpace
    Dim objWatchFolder As Outlook.Folder

    Set objNS = Application.GetNamespace("MAPI")
    Set objWatchFolder = objNS.GetDefaultFolder(olFolderInbox).Folders("Zip Files")

    Set objItems = objWatchFolder.Items
End Sub

Private Sub objItems_ItemAdd(ByVal Item As Object)
    If TypeOf Item Is Outlook.MailItem Then
        DeleteOlderThan6months Item
    End If
End Sub
'https://stackoverflow.com/questions/37060954/trouble-setting-the-subfolder
Sub DeleteOlderThan6months(ByVal Item As Object)
    '//  Declare variables
    Dim oFolder As Folder
    Dim Date6months As Date
    Dim ItemsOverMonths As Outlook.Items
    Dim DateToCheck As String
    Dim olNs As Outlook.NameSpace
    Dim Inbox  As Outlook.MAPIFolder
    Dim oItem As Object
    Dim i As Long

    '// set your inbox and subfolder
    Set olNs = Application.GetNamespace("MAPI")
    Set Inbox = olNs.GetDefaultFolder(olFolderInbox)
    Set oFolder = Inbox.Folders("Zip Files")

    Date6months = DateAdd("d", -1, Now())
    Date6months = Format(Date6months, "mm/dd/yyyy")

    DateToCheck = "[Received] <= """ & Date6months & """"
    Set ItemsOverMonths = oFolder.Items.Restrict(DateToCheck)

'    // Loop through the Items in the folder backwards
    For i = ItemsOverMonths.Count To 1 Step -1
        Set oItem = ItemsOverMonths.Item(i)
        If TypeOf oItem Is Outlook.MailItem Then
            Debug.Print oItem.Subject
            oItem.Delete
        End If
    Next

    Set ItemsOverMonths = Nothing
    Set oFolder = Nothing

End Sub

Tested on Outlook 2010.