Dedupe(): Removes duplicate emails from currently active Outlook folder by comparing the Sent Dates of emails and removing emails with duplicate sent dates.

dedupe.vba

Sub dedupe()
    
    Dim ol As New Outlook.Application
    Dim dates As Collection
    Dim mbox As Outlook.Folder
    Set dates = New Collection
    Set mbox = ol.ActiveExplorer.CurrentFolder
    
    For Each msg In mbox.Items
        msgDate = msg.SentOn
        Debug.Print msgDate
        flag = 0
        For i = 1 To dates.Count
            If msgDate = dates.Item(i) Then
                msg.Delete
                flag = 1
            End If
        Next i
        If flag = 0 Then dates.Add msg.SentOn
    Next msg
    
    Set dates = New Collection

End Sub