Sub copie()
Dim WBKS As Workbook, Source
Set WBKS = Workbooks.Open(Filename:="\\C\Downloads\fichiers\EXPORT BILL.xlsx")
ThisWorkbook.Sheets.Add.Name = "BILL"
Source = WBKS.Sheets(1).Cells(1).CurrentRegion.Value2
ThisWorkbook.Sheets("BILL").Cells(1).Resize(UBound(Source, 1), UBound(Source, 2)) = Source
End Sub