Private Sub CommandButton1_Click()

Dim MasterList As New Dictionary
Dim iListCount As Integer
Dim x As Variant
Dim iCtr As Integer
Dim v As Variant
Dim counter As Integer, i As Integer
counter = 0

With Sheets("Sheet2")
.Range("M:M").ClearContents
.Range("S:S").ClearContents

Sheets("Sheet1").Range("C:C").Copy
Sheets("Sheet2").Range("M1").Select
ActiveSheet.Paste


Sheets("Sheet1").Range("X:X").Copy
Sheets("Sheet2").Range("S1").Select
ActiveSheet.Paste

Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual

' Get count of records in master list
iListCount = .Cells(Rows.Count, "A").End(xlUp).Row
'Load Dictionary:
For iCtr = 1 To iListCount
    v = .Cells(iCtr, "A").Value
    If Not MasterList.Exists(v) Then MasterList.Add v, ""
Next iCtr

'Get count of records in list to be deleted
iListCount = .Cells(Rows.Count, "M").End(xlUp).Row

' Loop through the "delete" list.
    For iCtr = iListCount To 1 Step -1
        If MasterList.Exists(.Cells(iCtr, "M").Value) Then
            .Cells(iCtr, "M").Delete shift:=xlUp
            .Cells(iCtr, "S").Delete shift:=xlUp
        End If
    Next iCtr
  End With

Application.ScreenUpdating = True
Application.Calculation = xlCalculationAutomatic

MsgBox "Done!"
End Sub