1.double click Tchat. 2.choose chart-axis page. 3.choose axis: left radiobutton. 4.choose labels page. and set then datetime format is 'yyyy-mm-dd hh:nn:ss.zzz' 5.set labels round first is false. 6. chose axis :bottom radiobutton. 7.choose labels page. and set then datetime format is 'yyyy-mm-dd hh:nn:ss.zzz' 8.set labels round first is false. 9.select the line(sample : seriel1) double click. 10.select general page. 11.set horizontal axis : to datetime. that's ok! :)