Option Explicit
Sub Test()
Dim rngLotId As Excel.Range
Dim rngConfirmId As Excel.Range
Dim strWhat As String
strWhat = Trim$(InputBox("Bitte geben Sie eine Losnummer ein:"))
If Len(strWhat) = 0 _
Then Exit Sub
With Worksheets("Vorgabedatei").Range("A1:A100")
Set rngLotId = .Find( _
What:=strWhat, _
LookIn:=xlValues, _
LookAt:=xlWhole, _
SearchOrder:=xlByColumns, _
MatchCase:=False)
If Not rngLotId Is Nothing Then
Dim strFirstAddr As String
strFirstAddr = rngLotId.Address
Do
Set rngConfirmId = rngLotId.Worksheet.Cells(rngLotId.Row, "C")
Debug.Print "LotId: '"; rngLotId.Value; "', ConfirmId: '"; rngConfirmId.Value; "' (Row: "; CStr(rngLotId.Row); ")"
Set rngLotId = .FindNext(After:=rngLotId)
Loop While rngLotId.Address <> strFirstAddr
End If
End With
End Sub