Sub фильтр()

    Dim tPath As String
    Dim wbOp As Workbook

    tPath = ""
    tPath = ThisWorkbook.Path
    Set wbOp = Workbooks.Open(Filename:=tPath & "\1.xlsx")
    With wbOp
        Application.DisplayAlerts = 0
        If ActiveWorkbook.MultiUserEditing Then
            .ExclusiveAccess
        End If
        .Sheets("Лист1").Unprotect Password:="666"
        If ActiveSheet.FilterMode Then ActiveSheet.ShowAllData
        .Sheets("Лист1").Protect Password:="666", UserInterfaceOnly:=True, _
           DrawingObjects:=True, Contents:=True, Scenarios:=True, _
           AllowFormattingCells:=True, AllowFormattingColumns:=True, _
           AllowFormattingRows:=True, AllowSorting:=True, AllowFiltering:=True
        .SaveAs AccessMode:=xlShared
        Application.DisplayAlerts = 1
    End With
End Sub

dd = wbOp.Sheets("Лист1").UsedRange.Rows.Count