This is the offending VBA:
ActiveSheet.Sort.SortFields.Clear
    ActiveSheet.Sort.SortFields.Add Key:=Range("B7:B" & LastRow), SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    ActiveSheet.Sort.SortFields.Add Key:=Range("C7:C" & LastRow), SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    With ActiveWorkbook.Worksheets("Equipment").Sort
        .SetRange Range("A6:AM" & LastRow)
        .Header = xlYes
        .MatchCase = False
        .Orientation = xlTopToBottom
        .SortMethod = xlPinYin
        .Apply
    End With
the Sortfields.Clear works - then excel crashes and restarts
It works on 2 Computers but not a 3rd
All are Windows 10 v17.09 Excel 2016 64 Bits

Does anyone know of known issues? We are going to re-install MS Office and run all available updates.