export sequence as media file

HI,

I want to export sequence as media file i have tried something but that did not generate any output file and even not giving any error message

   // app.project.activeSequence.exportAsMediaDirect( "D:\\amit.avi","D:\\output_preset.epr",app.encoder.ENCODE_IN_TO_OUT);

   //app.project.activeSequence.exportAsMediaDirect( "D:\\amit.avi","D:\\output_preset.epr",app.encoder.ENCODE_ENTIRE);

//app.project.activeSequence.exportAsMediaDirect( "D:\\amit.avi","D:\\output_preset.epr",app.encoder.ENCODE_WORKAREA);