Speeding Up An Auto-delete Macro

Delete rows where column A and B are duplicated.

However, this runs extremely slow. I had to stop it after about 10 min, as it only got to about row 1000 of 20,000.


Sub Delete_Dupes()
Dim rw1 As Long: rw1 = 1
Dim rwx As Long: rwx = rw1
Dim stepx As Integer
Dim co1 As Integer: co1 = 1
Dim co2 As Integer: co2 = 2
Dim bool1 As Boolean
Dim bool2 As Boolean
Dim bool As Boolean
Dim count As Integer
count = 0
Do Until Cells(rwx, co1) = ""
stepx = 1
If rwx > rw1 Then
On Error GoTo NewCrit
bool1 = IsError(Application.WorksheetFunction.Match(Cells(rwx, co1), Range(Cells(rw1, co1), Cells(rwx - 1, co1)), 0))
bool2 = IsError(Application.WorksheetFunction.Match(Cells(rwx, co2), Range(Cells(rw1, co2), Cells(rwx - 1, co2)), 0)).................