More efficient way to find and delete columns

No Joy
I'm using this now

Sub DelColumnNotInList2()
Dim i&, LC&, myrng1
Set myrng1 = Range("A1")
     Application.ScreenUpdating = False
     LC = Cells.Find("*", , , , xlByColumns, xlPrevious).Column
For i = LC To 1 Step -1
    If InStr("Removed", Cells(1, i).Text) = 0 Then
 
        If myrng1 Is Nothing Then
                Set myrng1 = Cells("1", i)
            Else
                Set myrng1 = Union(myrng1, Cells("1", i))
            End If
    End If
Next i
        If Not myrng1 Is Nothing Then
            myrng1.EntireColumn.Delete
        End If
        Application.ScreenUpdating = True
End Sub

And I get Runtime Error 1004 Range Class failed on the .EntireColumn.Delete line.
Sorry for the trouble.
If I don't include the Set myrng1 piece at the start it throws up the object not defined error.