Soori, M., Arezoo, B. and Habibi, M., 2014. Virtual machining considering dimensional, geometrical and tool deflection errors in three-axis CNC milling machines. Journal of Manufacturing Systems, 33(4), pp.498-507.Virtual manufacturing system can provide useful means for product to be manufactured without the need of physical testing on the shop floor. As a result, the time and cost of part production can be decreased. there are different error sources in machine tools such tool deflection, geometrical deviations of moving axis and thermal distortion of machine tool structures. Some of these errors can be decreased by controlling machining process and environmental parameters. However other errors like tool deflection and geometrical errors which have a big portion of the total error, need more attention. This paper present a virtual machining system in order to enforce tool deflection, dimensional and geometrical errors in three-axis milling operations. The system receives 21 dimensional and geometrical errors of a machine tool and machining codes of a specific part as input. The output of the system is modified codes which will produce actual machined part in virtual environment.