GrapeCity.ActiveReports.Export.Excel.Section.XlsExport docexp = new GrapeCity.ActiveReports.Export.Excel.Section.XlsExport();
docexp.AutoRowHeight = true;
docexp.DisplayGridLines = true;
docexp.FileFormat = GrapeCity.ActiveReports.Export.Excel.Section.FileFormat.Xls95; //or Xls97Plus or Xlsx
docexp.MinColumnWidth = 3;
docexp.MinRowHeight = 1;
docexp.MultiSheet = true;
docexp.RemoveVerticalSpace = true;
docexp.UseCellMerging = false;
docexp.Export(this.viewer1.Document, Application.StartupPath + "\\x.xls");