How to Import C# DLL into MQL5 script

External question — Stack Overflow Stack Exchange Author: Yashar Safarzadeh Original post: https://stackoverflow.com/questions/63071560 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. I want to import following C# code which works fine as a dll into MQL5. would you please help me how to do the binding? (I am using Visual Studio 2015). using System; using System.Collections.Generic; using System.Linq; using System.Windows.Forms; namespace Keygen { static class Program { /// <summary> /// The main entry point for the application. /// </summary> [STAThread] static void Main() { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new Form2()); } } } The MQL5 code is: #property strict #import "Keygen.dll" void Program(); #import //+------------------------------------------------------------------+ //| Script program start function | //+------------------------------------------------------------------+ void OnStart() { //--- Program(); } //+-- ----------------------------------------------------------------+ after compiling in mql5 I get following the error: Cannot find 'Program' in 'Keygen.dll' unresolved import function call

External answer — Stack Overflow Stack Exchange Author: Yashar Safarzadeh Original post: https://stackoverflow.com/a/63152531 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. I solved this problem by putting the 64bit dll file in "Libraries" folder of MT5 Terminal and changing the MQL code like this. #import "Keygen.dll" //+------------------------------------------------------------------+ //| Script program start function | //+------------------------------------------------------------------+ void OnStart() { Program::Main(); } //+------------------------------------------------------------------+

External answer — Stack Overflow Stack Exchange Author: Ondrej Hlouzek Original post: https://stackoverflow.com/a/69183900 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. I had the same problem. And finally I figured it out. Assembly name, default namespace in project property and namespace name must be the same! Then everything will work as it should.