Fehler in Makro?

Sub delete()
Dim wb1 As Excel.Workbook
Set wb1 = ThisWorkbook
Dim wb2 As Excel.Workbook
Set wb2 = Workbooks.Open("C:\Users\Test\Desktop\test.xls")
letzteZeileZiel = wb1.Sheets(1).Cells(Rows.Count, 1).End(xlUp).Row
letzteZeileQuelle = wb2.Sheets(1).Cells(Rows.Count, 5).End(xlUp).Row
For x = letzteZeileZiel To 5 Step -1
For y = letzteZeileQuelle To 2 Step -1
If wb1.Sheets(1).Range("A" & x).Value = wb2.Sheets(1).Range("A" & y).Value Then
If wb1.Sheets(1).Range("A" & x).Interior.ColorIndex = 3 Then
wb2.Sheets(1).Range("A" & y).EntireRow.delete Shift:=xlUp
End If
End If
Next
Next
End Sub