How to create autoreply with number of unread mails in inbox using Outlook VBA?

I am trying to trigger a script with rules to send an autoreply.

"Hi thanks for your mail, your mail has been placed in a queue there are XX number of e-mails in front of you, we will answer as soon as possible."

The XX should be the number of unread e-mails.

I found outlook automated reply with unread message count:

Private Sub myOlItems_ItemAdd(ByVal Item As Object)

End Sub

Sub AutoResponse(objmsg As Outlook.MailItem)

    ' define my reply message
    Dim objReply As MailItem
    ' let's get ourselves the inbox!
    Dim inbox As MAPIFolder
    Set inbox = Application.GetNamespace("MAPI"). _
    GetDefaultFolder(olFolderInbox)

    ' Let's get this reply going!
    Set objReply = objmsg.Reply
    ' Subject Re: their subject. Standard
    objReply.Subject = "Re: " & objReply.Subject
    ' Body - you define this, use the variable for the unread count in inbox
    objReply.Body = "Your email has been received. I currently have " & inbox.UnReadItemCount & " unread emails in my inbox and I will get yours as soon as I can"

    ' Send this thing!
    objReply.Send
    ' Reset
    Set objReply = Nothing

End Sub

It doesn't work.

I am on Outlook 2016, with an exchange mail server.

Solution

Your Items.ItemAdd Event is not set correctly, Try the flowing code without Outlook rule, Make sure to restart your Outlook

Private WithEvents Items As Outlook.Items

Private Sub Application_Startup()
    Dim olNs As Outlook.NameSpace
    Dim Inbox  As Outlook.MAPIFolder

    Set olNs = Application.GetNamespace("MAPI")
    Set Inbox = olNs.GetDefaultFolder(olFolderInbox)
    Set Items = Inbox.Items
End Sub

Private Sub Items_ItemAdd(ByVal Item As Object)

    If TypeOf Item Is Outlook.mailitem Then
        AutoResponse Items
    End If

End Sub

Private Sub AutoResponse(Item As Outlook.mailitem)
    Dim Reply As Outlook.mailitem ' Reply msg
    Dim Inbox As Outlook.MAPIFolder ' Inbox

    Set Inbox = Application.GetNamespace("MAPI") _
                .GetDefaultFolder(olFolderInbox)

    ' Let's get this reply going!
    Set Reply = Item.Reply
    ' Subject Re: their subject. Standard
    Reply.subject = Reply.subject

    ' Body - you define this, use the variable for the unread count in inbox
    Reply.HTMLBody = "Your email has been received. I currently have " & _
                      Inbox.UnReadItemCount & _
              " unread emails in my inbox and I will get yours as soon as I can"

    ' Send this thing!
    Reply.Send
    ' Reset
    Set Reply = Nothing

End Sub