How to debug the .NET Windows Service OnStart method?

Question

I have code written in .NET that only fails when installed as a Windows service. The failure doesn\'t allow the service to even start. I can\'t figure out how I can step int

Answer 1

You can also try System.Diagnostics.Debugger.Launch() method. It helps in taking the debugger pointer to the specified location and you can then debug you code.

Before this step please install your service.exe using the command line of Visual Studio command prompt - installutil projectservice.exe

Then start your service from the Control Panel -> Administrative Tools -> Computer Management ->Service and Application -> Services -> Your Service Name

Answer 2

If you add Debugger.Launch() in your OnStart method and it doesn't work, you could have the same issue I had, namely, the exception was occurring in the constructor so the OnStart was never called. (head slap)

(sorry if this should have been a comment on someone else' answer, but i don't have enough cred to make comments)

Answer 3

I have an interesting way of doing this I add another Configuration called DebugNoService

  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'DebugNoService|AnyCPU' ">
    <OutputPath>.\</OutputPath>
    <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
    <BaseAddress>285212672</BaseAddress>
    <CheckForOverflowUnderflow>false</CheckForOverflowUnderflow>
    <ConfigurationOverrideFile>
    </ConfigurationOverrideFile>
    <DefineConstants>DEBUG;TRACE;DEBUGNOSERVICE</DefineConstants>
    <DocumentationFile>
    </DocumentationFile>
    <DebugSymbols>true</DebugSymbols>
    <FileAlignment>4096</FileAlignment>
    <NoStdLib>false</NoStdLib>
    <NoWarn>
    </NoWarn>
    <Optimize>false</Optimize>
    <RegisterForComInterop>false</RegisterForComInterop>
    <RemoveIntegerChecks>false</RemoveIntegerChecks>
    <TreatWarningsAsErrors>false</TreatWarningsAsErrors>
    <WarningLevel>4</WarningLevel>
    <DebugType>full</DebugType>
    <ErrorReport>prompt</ErrorReport>
    <UseVSHostingProcess>false</UseVSHostingProcess>
  </PropertyGroup>

I use the #if directive. ProjectInstaller.cs

#if !DEBUGNOSERVICE    
   static void Main()
   {
      System.ServiceProcess.ServiceBase[] ServicesToRun;
      .....
   }
#endif

I add a windows form and I also wrap the windows form in

#if DEBUGNOSERVICE
...
static void Main() 
{
    Form     form;

    Application.EnableVisualStyles();
    Application.DoEvents();

    form = new <the name of the form>();

    Application.Run(form);
}
...
#endif

depending on the configuration selected the code either runs as a windows form application that can be easily debugged or as a service.

If seems like a lot of work but it has always worked and makes debugging the code very very easy. You can have all sorts of output added to the form so you can watch it run.

Answer 4

Try adding Debugger.Break inside the problematic method. When the service will start an exception will be thrown and widows should offer to debug it using visual studio.