Does not contain a static 'main' method suitable for an entry point

Question

I began organizing my code to day into seperarate .cs files, and in order to allow the methods that work with the UI to continue to do so I would create the .cs code under the same namespace and public partial class name so the methods could be inter-operable.

My header look like this in four files, including my main core file that calls:

public shell()
{
InitializeComponent(); 
}

Header area of .cs files that work with the UI (and seem to be causing this new conflict):

using System;
using System.Windows.Forms;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.IO;
using System.Data.SqlServerCe;
using System.Diagnostics;
using System.Threading;
using System.Collections.Specialized;
using System.Net;
using System.Runtime.InteropServices;
using watin = WatiN.Core;
using WatiN.Core.Native.InternetExplorer;
using System.Web; 


namespace WindowsFormsApplication1
{

    public partial class shell : Form
    {

Now when I try to debug/preview my application (BTW this is a Windows Application within Visual Studio 2010 Express) I get this error message:

Does not contain a static 'main' method suitable for an entry point

I looked in the application properties in Application->Startup object, but it offers me no options. How can I inform the application to begin at the .cs file that has my InitializeComponent(); command?

I've looked around so far without a solution.
The properties on each .cs file are set to 'Compile'.
I do not see an App.xaml file in my Solutions explorer but I do see a app.config file.

I'm still very new and this is my first attempt at an organizing method with c# code.

To be honest I don't see a method called Main anywhere in my code. I've been working on this project for a couple of months now too. — atwellpub, Mar 07 '12 at 19:29
You need a static method called `main`, with the correct signature. That's how the compiler knows how to start your program. — David Heffernan, Mar 07 '12 at 19:30
Is there a way I can manually program the solution where to start? I'm confused to how it cannot find a static 'Main' method when I can't seem to find any instruction in the code telling it to look for a 'Main' method. I am very new at c#. --- [edit] - @David Hefferman , Would you elaborate on what you mean by 'the correct signature'? — atwellpub, Mar 07 '12 at 19:32
The way you tell the compiler where your program starts is by adding a static function named `main` with the appropriate signature. — David Heffernan, Mar 07 '12 at 19:33
try adding something like this to your project `[STAThread] static void Main(string[] args) { Application.Run(new shell()); }` — L.B, Mar 07 '12 at 19:35
Hey @L.B Alright! Worked and I'm back in business. Thanks to everyone that helped! — atwellpub, Mar 07 '12 at 19:44

score 173 · Answer 1 · edited Aug 18 '23 at 09:11

173

I was looking at this issue as well, and in my case the solution was too easy. I added a new empty project to the solution. The newly added project is automatically set as a console application. But since the project added was a 'empty' project, no Program.cs existed in that new project. (As expected)

All I needed to do was change the output type of the project properties to Class library.

edited Aug 18 '23 at 09:11

SuperDJ

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answered Jun 06 '12 at 19:01

Arne

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A bit overkill of a solution, I think. It would be a lot easier to follow @eyossi's solution. – TimWagaman Jun 07 '12 at 15:38
2

But did you want a console application or a class library? Don't just change the type of application to fix an error; know what the error is telling you. Console applications need an entry point (`static void main()`) to determine where to start executing code; class libraries don't - they are called by other libraries that are already executing. – KyleMit Feb 05 '14 at 16:31
This is the overkill version of what @pixaloop suggests. After reading this answer, I remembered that when adding an Empty project defaults the output to Console. So I just went and changed it. Wanted to post it as an answer (as it is much simpler), but saw that someone else already did. – EternalWulf Oct 03 '14 at 11:36
Thanks man. That would have been the last place I would have looked! – eaglei22 Jul 16 '15 at 19:55
1

Not overkill at all. This was the exact issue in my situation. The compiler was looking for a `main` in my two other projects that were *Console Application*s just like the StartUp project. Changing those two "assisting" projects to *Class Library* in their Properties screen fixed it immediately. – Ctrl S Nov 20 '18 at 18:23

score 111 · Answer 2 · answered Aug 06 '14 at 09:01

111

Change the Output Type under the Project > Properties to that of a “Class Library”. By default, this setting may have been set to a “Console Application”.

answered Aug 06 '14 at 09:01

Automationtested

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This is exactly what I did, works perfect. If you added an 'Empty' project, it defaults to Console. – EternalWulf Oct 03 '14 at 11:35
Thank you, this worked perfectly for me. One more thing I would like to add is that, when you right click your project and go to the properties, the "Output Type" will be available under "General". So the whole path is basically [Your Project Name] > Properties > Application > General > Output Type – Brookie_C Jan 14 '22 at 20:58

score 42 · Answer 3 · edited Mar 11 '20 at 23:25

42

I had this error and solved it using this solution.

Right click on the project
Select "Properties"
Set "Output Type" to "Class Library".

edited Mar 11 '20 at 23:25

pushkin

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answered Jun 22 '19 at 11:44

Ali Ahmadi

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yeah but you need another project to debug the class library. Defeats the purpose – Fandango68 Jan 12 '20 at 06:33
Worked for me, because I was only getting this error on a utility project, not the startup project – Joshua Swain Dec 11 '20 at 14:38
This is correct. If you use something like "Hello World" to start your project, and took it out , you must to face this way. – Martin Zamora Jun 18 '21 at 04:13

score 28 · Answer 4 · edited Feb 05 '14 at 16:32

28

Try adding this method to a class and see if you still get the error:

[STAThread]
static void Main()
{
}

edited Feb 05 '14 at 16:32

KyleMit

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answered Jun 06 '12 at 19:06

eyossi

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In my case, I wanted a console app. So adding the entry point to my class did the trick. I'm a VS 2022 noob but I liked the old console templates better. This is confusing and console apps should just work out of the box without writing any code. Bad UI decision by Microsoft IMO. – Vance McCorkle Feb 16 '22 at 05:45
This helped me. My Main() method wasn't static. – tolache Aug 03 '22 at 08:00

bereket gebredingle · Answer 5 · 2019-12-09T01:59:26.580

15

Edit .csproj file

<OutputType>Library</OutputType>

cheers !

edited Dec 09 '19 at 01:59

answered Nov 09 '19 at 02:12

bereket gebredingle

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1

This actually works, but it has to be `Library` (with a capital `L`) – detunized Dec 08 '19 at 11:26
2

It is supposed to be the default in .net core https://learn.microsoft.com/fr-fr/visualstudio/msbuild/common-msbuild-project-properties?view=vs-2019 Turns out that when your project is the default value Library is overriden to Exe during build. Resolving SDK 'Microsoft.NET.Sdk.Web.ProjectSystem'... Property reassignment: $(OutputType)="Exe" (previous value: "Library") – Romain Hautefeuille May 28 '20 at 10:01
2

Instead of editing .csproj, you can use the GUI in Visual Studio 2019. 1. Select the project in the Solution Explorer 2. Click "Project" --> " Properties" from the main toolbar 3. Output type: Class Library 4. Save – Joshua Swain Dec 11 '20 at 14:43

score 14 · Answer 6 · edited Feb 05 '14 at 16:34

If you don't have a file named Program.cs, just add a new Class and name it Program.cs.

Then paste this code:

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Windows.Forms;

 namespace Sales {
     static class Program {

         /// <summary>
         /// The main entry point for the application.
         /// </summary>
         [STAThread]
         static void Main() {
             Application.EnableVisualStyles();
             Application.SetCompatibleTextRenderingDefault(false);
             Application.Run(new Form1());
         }
     }

 }

score 14 · Answer 7 · answered Jun 21 '16 at 16:37

14

Select App.xaml and display its properties. Set Build Action to ApplicationDefinition.
App.xaml and its corresponding *.cs file must be placed into the root directory of the *.csproj file, i. e. not into a "Source" folder.

answered Jun 21 '16 at 16:37

Roman Volkov

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2

This is the case for me. I ctrl+c copied a App.xml into the project and the build action was set to "Page". – Jacky Cheng May 30 '18 at 03:42

score 12 · Answer 8 · answered Feb 17 '20 at 16:18

12

Had this problem in VS 2017 caused by:

static async Task Main(string[] args)

(Feature 'async main' is not available in C# 7.0. Please use language version 7.1 or greater)

Adding

<LangVersion>latest</LangVersion>

to app.csproj helped.

answered Feb 17 '20 at 16:18

Jan

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I had the same, I think because I initially created the solution with VS2019 and then tried to open it in VS2017. Mine is a dotnetcore console app. – trebor Jul 28 '20 at 14:04
Add inside https://codez.deedx.cz/posts/csharp-async-main/ – user1220497 Mar 18 '21 at 06:03

score 8 · Answer 9 · answered Nov 05 '14 at 11:41

8

If you do have a Main method but still get this error, make sure that the file containing the Main method has "Build action" set to "Compile" and "Copy to ouput directory" set to "Do not copy".

answered Nov 05 '14 at 11:41

simonbs

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Thank you! Perhaps in another couple of hours, I'd realize that I couldn't generate a syntax error and thus looked there.. – Gerard ONeill Feb 16 '16 at 23:33

score 7 · Answer 10 · edited Dec 17 '22 at 19:59

7

Make sure you are not using void with async like

static async void Main(string[] args)

If yes, then change void to Task like

static async Task Main(string[] args)

edited Dec 17 '22 at 19:59

Dour High Arch

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answered Sep 11 '22 at 21:43

Gaurang Naik

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score 6 · Answer 11 · answered Sep 23 '19 at 13:45

For me, the error was actually produced by "Feature 'async main' is not available in C# 7.0. Please use language version 7.1 or greater". This issue was resulting in the "Does not contain a static 'main' method suitable for an entry point" message in the Error List, but the Output window showed the "not available" error. To correct this, I changed the language version from 'C# latest minor version (default)' to 'C# latest minor version (latest)' under Advanced Build Settings.

Good catch. The actual version issue is only stated in output window — int-i, Dec 02 '19 at 21:42

score 4 · Answer 12 · answered Dec 30 '12 at 07:42

4

hey i got same error and the solution to this error is just write Capital M instead of small m.. eg:- static void Main() I hope it helps..

answered Dec 30 '12 at 07:42

Chetan Soni

41
1

score 2 · Answer 13 · answered Jul 01 '19 at 05:26

2

Salaam, I have both Visual Studio 2017 and Visual Studio 2019

Visual Studio 2019 does not show this error but 2017 does. Try Installing Visual Studio 2019.

Visual Studio 2017

Visual Studio 2019

answered Jul 01 '19 at 05:26

Ali Jamal

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Siddhi Kamat · Answer 14 · 2022-03-28T13:36:18.537

2

After placing the above code in Program.cs, follow below steps

Right click on the project

Select Properties

Set Output Type to Windows Application

Startup object : namepace.Program

edited Mar 28 '22 at 13:36

answered May 17 '20 at 05:51

Siddhi Kamat

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How do you set startup object in VSCode ?? – Sold Out Jun 11 '21 at 15:33
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@SoldOut This might help you [visual-studio-code-program-has-more-than-one-entry-point-defined](https://stackoverflow.com/questions/47152454/visual-studio-code-program-has-more-than-one-entry-point-defined) – Siddhi Kamat Aug 06 '21 at 17:14
Inerestin'... thank you :) But why in the world does it erase your name with '@' ?? – Sold Out Aug 09 '21 at 07:22

score 2 · Answer 15 · answered Jul 16 '21 at 18:23

2

Just right click on project and select properties and then set Output type on Class Library

answered Jul 16 '21 at 18:23

Ata Hoseini

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score 2 · Answer 16 · answered Mar 07 '12 at 19:32

2

Looks like a Windows Forms project that is trying to use a startup form but for some reason the project properties is set to startup being Main.

If you have enabled application framework you may not be able to see that Main is active (this is an invalid configuration).

answered Mar 07 '12 at 19:32

Joshua

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I'd be interested in hearing a little more about Application Framework setting and anything that might tell the software to look for Main() when a Main method did not seem to exist anywhere. – atwellpub Mar 07 '12 at 19:46
I believe the Application Framework setting only applies to VB.NET. C# Forms applications always have "main" as an entry point. – A. Wilson Mar 07 '12 at 19:59

score 1 · Answer 17 · answered Jun 20 '17 at 11:06

When you want to allow paramaters to be specified from the command, they must look like this:

 [STAThread]
 static void Main(params string[] paramaters)
 {

you cannot specify more than one paramater, otherwise this will also cause the error reported above.

Madison Haynie · Answer 18 · 2018-03-20T08:29:26.270

1

For some others coming here:

In my case I had copied a .csproj from a sample project which included <EnableDefaultCompileItems>false</EnableDefaultCompileItems> without including the Program.cs file. Fix was to either remove EnableDefaultCompileItems or include Program.cs in the compile explicitly

edited Mar 20 '18 at 08:29

answered Mar 08 '18 at 14:35

Madison Haynie

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yash patel · Answer 19 · 2018-04-21T05:16:11.740

hellow your main class was deleted so add new class that name set as Main.cs and pest that code or if porblem in window so same problem on that

using System;
using System.Collections.Generic;
using System.Linq;
using Foundation;
using UIKit;

namespace your_PKG_name.iOS
{
       public class Application
        {
            // This is the main entry point of the application.
            static void Main(string[] args)
            {
                // if you want to use a different Application Delegate class from "AppDelegate"
                // you can specify it here.
                UIApplication.Main(args, null, "AppDelegate");

            }
        }
}

h'whoops, accidentally dragged my Main file out of the iOS project. Thanks — Dan Beaulieu, Sep 27 '19 at 23:05

score 1 · Answer 20 · answered Sep 18 '18 at 12:00

A valid entry looks like:

public static class ConsoleProgram
    {
        [STAThread]
        static void Main()
        {
            Console.WriteLine("Got here");
            Console.ReadLine();
        }
    }

I had issues as I'm writing a web application, but for the dreadly loading time, I wanted to quickly convert the same project to a console application and perform quick method tests without loading the entire solution.

My entry point was placed in /App_Code/Main.cs, and I had to do the following:

Set Project -> Properties -> Application -> Output type = Console Application
Create the /App_Code/Main.cs
Add the code above in it (and reference the methods in my project)
Right click on the Main.cs file -> Properties -> Build Action = Compile

After this, I can set the output (as mentioned in Step 1) to Class Library to start the web site, or Console Application to enter the console mode.

Why I did this instead of 2 separate projects?

Simply because I had references to Entity Framework and other specific references that created problems running 2 separate projects.

For easier solutions, I would still recommend 2 separate projects as the console output is mainly test code and you probably don't want to risk that going out in production code.

score 1 · Answer 21 · answered Feb 28 '19 at 10:27

1

If you are using a class library project then set Class Library as output type in properties under application section of project.

answered Feb 28 '19 at 10:27

Manveer Singh

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score 1 · Answer 22 · answered Aug 27 '21 at 08:07

Another situation where this occur is when someone (unintentionally) changes Build Action for Program.cs. The value for Build Action should be C# compiler.

I accidentally changed Build Action to None, which removed program.cs from the project and therefore wasn't included when compile started.

Hakan Bayazıt · Answer 23 · 2022-08-17T06:25:22.247

1

Did you accidentally remove the entire Program.cs file? If you have removed,

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ListWievKullanımı
{
   static class Program
   {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
    }
}

This might work for you.

edited Aug 17 '22 at 06:25

answered Nov 19 '21 at 20:37

Hakan Bayazıt

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Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community Nov 19 '21 at 21:09

score 1 · Answer 24 · answered Oct 12 '22 at 19:16

I got this error when using the command Build Docker Image in Visual Studio 2022.

error CS5001: Program does not contain a static 'Main' method suitable for an entry point

The project built perfectly well in Windows but I tried to build a Linuxcontainer. Switching to Output Type Class Library solved the error but Docker Compose gave me this error instead:

CTC1031 Linux containers are not supported for

https://stackoverflow.com/a/74044317/3850405

I tried explicitly using a Main method like this but it did not work:

namespace WebApplication
{
    public class Program
    {
        public static void Main(string[] args)
        {

I have no idea why but this solved it for me:

Gives error:

FROM mcr.microsoft.com/dotnet/aspnet:6.0 AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:6.0 AS build
WORKDIR /src
COPY ["src/Services/Classification/ClassificationService.Api/ClassificationService.Api.csproj", "Services/Classification/ClassificationService.Api/"]

RUN dotnet restore "Services/Classification/ClassificationService.Api/ClassificationService.Api.csproj"
COPY . .
WORKDIR "/src/Services/Classification/ClassificationService.Api"
RUN dotnet build "ClassificationService.Api.csproj" -c Release -o /app/build

Works:

FROM mcr.microsoft.com/dotnet/aspnet:6.0 AS base
WORKDIR /app
EXPOSE 80
EXPOSE 443

FROM mcr.microsoft.com/dotnet/sdk:6.0 AS build
WORKDIR /src
COPY ["src/Services/Classification/ClassificationService.Api/ClassificationService.Api.csproj", "src/Services/Classification/ClassificationService.Api/"]

RUN dotnet restore "src/Services/Classification/ClassificationService.Api/ClassificationService.Api.csproj"
COPY . .
WORKDIR "/src/src/Services/Classification/ClassificationService.Api"
RUN dotnet build "ClassificationService.Api.csproj" -c Release -o /app/build

Notice the double /src in the working example.

I read that you had to place the Dockerfile at the same level as .sln file but in my case the files are separated by four levels.

https://stackoverflow.com/a/63257667/3850405

Don't know but this resolved my problem. – Dany Mar 01 '23 at 10:45 — Dany, Mar 01 '23 at 10:45

score 0 · Answer 25 · answered Mar 29 '16 at 11:05

0

I too have faced this problem. Then I realized that I was choosing Console Application(Package) rather than Console Application.

answered Mar 29 '16 at 11:05

Prasad

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score 0 · Answer 26 · answered Sep 20 '16 at 08:11

0

I am using Visual Studio and also had this problem. It took me some time, but in my program it was caused because I accidentally deleted a Class named "Program" that is generated automatically.

answered Sep 20 '16 at 08:11

MaChaToc

139
1
12

score 0 · Answer 27 · answered Oct 06 '16 at 20:43

For future readers who faced same issue with Windows Forms Application, one solution is to add these lines to your main/start up form class:

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new MyMainForm());
    }

Then go to project properties > Application > Startup Object dropdown, should see the namespace.MyMainForm, select it, clean and build the solution. And it should work.

score 0 · Answer 28 · answered Feb 24 '17 at 22:55

0

Check to see if the project is set as the "Startup Project"

Right click on the project and choose "Set as Startup Project" from the menu.

answered Feb 24 '17 at 22:55

James Wierzba

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score 0 · Answer 29 · answered Mar 15 '18 at 15:57

If you are like me, then you might have started with a Class Library, and then switched this to a Console Application. If so, change this...

namespace ClassLibrary1
{
    public class Class1
    {
    }
}

To this...

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
        }
    }
}

score 0 · Answer 30 · answered Nov 17 '21 at 14:36

0

If you use Visual Studio Code change Project Sdk="Microsoft.NET.Sdk.Web" to Project Sdk="Microsoft.NET.Sdk" on csproj file.

answered Nov 17 '21 at 14:36

Elseif

1
1

score 0 · Answer 31 · answered Dec 04 '22 at 13:55

0

Add

static async Task Main(string[] args)
{
}

instead of

static async void Main(string[] args)
{
}

its work for me.

answered Dec 04 '22 at 13:55

Ishara Samintha

460
6
8

score 0 · Answer 32 · edited May 23 '17 at 10:31

0

If you do indeed have a public static main method it could be your build settings as explained in this question: Troubleshooting "program does not contain a static 'Main' method" when it clearly does...?

edited May 23 '17 at 10:31

Community

1
1

answered Mar 07 '12 at 19:26

A. Wilson

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score -1 · Answer 33 · answered Nov 24 '20 at 04:00

-1

Perhaps unintentional, but moving my docker file to the solution folder instead of the project eliminated the error. This was helpful when I still wanted to run the solution independently of docker

answered Nov 24 '20 at 04:00

ririvas

11

Does not contain a static 'main' method suitable for an entry point

33 Answers33

Edit .csproj file

Linked