So schaut meine Lösung aus.
Sub Initialize
Dim aktuellerServer As String
Dim db As NotesDatabase
Dim doc As NotesDocument,doc2 As NotesDocument
Dim view As NotesView
Dim starttime As String, endtime As String, suche As String
Dim dc As NotesDocumentCollection
Set session = New notessession
aktuellerServer = session.currentdatabase.server
If aktuellerServer = "" Then Exit Sub
Set db=session.currentDatabase
Set view=db.getView("(gemeinsametermine)")
Set doc=view.getfirstdocument
While Not (doc Is Nothing)
'ersten Wert auslesen
starttime=doc.StartDateTime(0)
endtime=doc.EndDateTime(0)
suche=starttime+" - "+endtime
Set dc = view.GetAllDocumentsByKey(suche, False)
If dc.Count > 1 Then
Call dc.StampAll("gemeinsam", "1")
End If
Set doc=view.GetNextDocument(doc)
Wend
End Sub