Benutzerdefinierter Typ nicht definiert

Public Sub SendSingleFiles()
Dim Files As VBA.Collection
Dim File As Scripting.File
Dim Mail As Outlook.MailItem
Dim Atts As Outlook.Attachments
'Alle Dateien aus diesem Verzeichnis senden
m_Send = "C:/Users/KW1_Test/"
'Gesendete Dateien hierhin verschieben
m_Done = "C:/Users/KW1_Test/Gesendet/"
'Empfänger
m_To = "xyz@gmail.com"
Set Files = GetFiles
If Files.Count Then
Set Mail = Application.CreateItem(olMailItem)
Set Atts = Mail.Attachments
For Each File In Files
Atts.Add File.Path
File.Move m_Done & File.Name
Next
Mail.To = m_To
Mail.CC = m_CC
Mail.Subject = "KW1"
Mail.Body = "Sehr geehrte Herr xyz," & vbCrLf & vbCrLf & "im Anhang finden Sie die aktuelle(n) xyz." & vbCrLf & vbCrLf & _
"Mit freundlichen Grüßen" &  "Dies ist eine automatisch generierte Nachricht." & vbCrLf & Date & "-" & Time
Mail.Send
Mail.OriginatorDeliveryReportRequested = True   'übermittlungsbestätigung
Mail.ReadReceiptRequested = True                'Lesebestätigung
End If
End Sub

Private Function GetFiles() As VBA.Collection
Dim Folder As Scripting.Folder
Dim Fso As Scripting.FileSystemObject
Dim Files As Scripting.Files
Dim File As Scripting.File
Dim List As VBA.Collection
Set List = New VBA.Collection
Set Fso = New Scripting.FileSystemObject
Set Folder = Fso.GetFolder(m_Send)
Set Files = Folder.Files
For Each File In Files
If (File.Attributes Or Hidden)  File.Attributes Then
List.Add File
End If
Next
Set GetFiles = List
End Function