static void Main(string[] args) { // Read our RTF document as string. string inpFile = @"..\..\example.txt"; string textString = File.ReadAllText(inpFile); string outFile = @"Result.html"; SautinSoft.RtfToHtml r = new SautinSoft.RtfToHtml(); // Specify some properties for output HTML document. r.OutputFormat = SautinSoft.RtfToHtml.eOutputFormat.HTML_5; r.Encoding = SautinSoft.RtfToHtml.eEncoding.UTF_8; r.TextStyle.Title = "Textual document."; try { r.OpenTextFromString(textString); r.ToHtml(outFile); // Open the result for demonstration purposes. System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(outFile) { UseShellExecute = true }); } catch (Exception e) { Console.WriteLine($"Error: {e.Message}"); Console.WriteLine("Press any key ..."); Console.ReadKey(); } }