Develop Reference

Create a Windows service without the use of a timer [duplicate]

I made a Window service and let it work automatically and under localsystem account, when the service starts it fires this message for me and then stops
The [service name] service on local computer started and then stopped. Some Services stop automatically if they are not in use by another services or programs.
What's the problem and what's the solution?

Either you are not starting any threads on the OnStart method to do work, or there is an exception raised within your OnStart method.
If an exception is thrown, it will appear in the Windows Event log. The Windows Event log is a good place to start in any case.
Generally an OnStart method looks like this:
Thread _thread;
protected override void OnStart(string[] args)
{
// Comment in to debug
// Debugger.Break()
// Do initial setup and initialization
Setup();
// Kick off a thread to do work
_thread = new Thread(new MyClass().MyMethod)
_thread.Start();
// Exit this method to indicate the service has started
}

This particular error message means what it says - that your service has started but then quite soon it exited for some reason. The good news is that your service is actually doing something, so you have the executable configured and running as a service properly.
Once started, for some reason it is quitting. You need to find out why this is. Add some debugging to tell you its up and running and known exit cases. If that doesn't reveal the problem then add some debugging to let you know it's still running and work backwards from when that stops.

Are you tracing out any debug information? Most likely an exception is being thrown during your initialization. I would trace out all your exceptions and use Debugview to view them.

I had a similar problem that occurred because my Event Logs were full and the service was unable to write to them. As such, it was impossible to debug by looking for messages in the Event Viewer. I put a try/catch and dumped the exception out to a file. I had to change the settings on my logs to fill as needed instead of every 7 days and this allowed the services to start.
Of course, the root of the problem for me is that I have a nVidia driver issue that is flooding my event logs and now I'm probably beating on the disk, but that's another issue.

Maybe you need to run the service as Local System Account. See this post by Srinivas Ganaparthi.

I had the same issue starting JBoss, then I changed the JAVA_HOME variable, it worked for me. It was the JBoss version that doesn't support the 1.6, it supports 1.5.

I had similar problem and it turned out in my case that the program simply crashed in OnStart method. It tried to read some file that it couldn't find but I suppose that any other program crash would give the same result. In case of Windows forms application you would get some error message but here it was just "your service started and stopped"
If you ever need, like me to read some files from the directory where Windows Service .exe is located, check this topic:
Getting full path for Windows Service

In my case, a method in my service, was being called recursively (as no terminate condition being true) and after specific time my service was being stopped.

WCF service hosted in Windows service - not working

I've created the WCF service and some simple WPF application consuming it. When I'm running the project from within Visual Studio, the WCF Test Client opens and the application works just fine, method defined in service work.
But I need to host this WCF service in a Windows Service. I've followed this, installed the services using Installutil.exe and the ran the service. Everything went fine, it's working.
Yet, when I'm trying to open the executable file with WPF application directly from the debug folder of the app, I'm getting this error:
zad8. has stopped working
After choosing the option to debug it with new instance of VS I get
XamlParseException occured in PresentationFramework.dll
The stack trace shows something like:
connection can't be started, because the target computer is actively refusing it
Do you have any idea what could go wrong?

Fortunately, I've managed to come up with solution. I think I should post it, maybe one day it will help somebody:)
I actually did two mistakes, but one of them was unfortunately caused by the mentioned tutorial (here) in connection with my temporary blackout.
In step 5, point 8 of this tutorial, there's an example of overriding OnStart() method:
protected override void OnStart(string[] args)
{
if (myServiceHost != null)
{
myServiceHost.Close();
}
myServiceHost = new ServiceHost(typeof(Service1));
myServiceHost.Open();
}
Beware, that Service1 is ambiguous in this context, because it's name of the Windows Service project class as well as the name of WCF Service class. It should be written with fully qualified name (here it is WcfServiceLibrary1.Service1). In my case, the service name was different, and I just put the Service1 in there in a hurry. Anyway..
In case, someone has it all behind and still encounters the same problem (with app stopped working), I think that you should try open the project in Visual Studio and try to debug the client consuming application as a new instance (right click on the project-> Debug -> Start as new instance...).
It might seem trivial, but when u hit F5 or Ctrl+F5 then even if u have only those project set as startup project, VS will host it's client anyway. In my case it did matter, because I needed to use isolation storage file. And as it was kept on the service side, then I had this file created in IIS server created by VS. Somehow, my method of creating such file had set FileMode.Open() and it was causing the crush, because in Windows Service it didn't exist and the new one couldn't be created and that was neccessary to run it correctly.
What's more it just showed me that this question couldn't be answered properly, cause the data I've provided was not enough and it was delicate.
Cheers:)

Application_start not working

I have written some code in the application_start() method in my global.asax file. It does not get called when I deploy my application on IIS server. The code is accessible when I run it in the .NET framework.
I've tried to restart the application many times, but it's still not working.
I've also tried the suggestion from the following link.
Application_Start not firing?

There are few things you need to know before you are trying to debug Appplication_Start. There are -
One : When the code executes and why it is almost impossible to debug by attaching to it.
The application start method is executed when the application pool starts and your website is being started up for the first time. If you deploy new deliverables to IIS, then IIS might restart it itself, but there is no guarantee that it will. So, deploying new codes does not guarantee that it will restart the pool and he execution of application start. You should restart your application pool to guarantee execution of application start.
While debugging IIS applications, Visual Studio attaches itself to a process something named w3wp.exe or similart (I forgot the actual executable name), which is the worker process and only available after, remember after, your application pool is up and your site is up. So, in other words, if you are seeing this in service list, then the application start has already been executed and attaching to it will not give you a chance to debug it. It is kind of a tug of war with time.
So, in other words, it is kind of impossible to debug application start unless you are very very quick.
Two, the solution 1 - With Dev Server
Launch your application in visual studio with Asp.net development server or IIS express, then you will be able to debug. But if you really want to debug on IIS, then check the next section
Two, the solution 2 - With IIS
There is a library in the name System.Diagnostics, Debuggerand it has a nice way to call debugger in code. You can read it here - http://msdn.microsoft.com/en-us/library/system.diagnostics.debugger.break(v=vs.110).aspx
Modify you application start with this -
public void Application_Start(){
....... //other codes
Debugger.Break() or Debugger.Launch()
}
When this line executes, IIS will halt execution, and will show you a debugger selector window (similar to the one attached), keep your solution open in vs and select that vs from the list, will be able to debug as usual... :)
In case you are using windows 8 and the debugger does not launch, read this article to enable it -
http://blogs.msdn.com/b/mapo/archive/2013/11/07/debugger-launch-not-displaying-jit-debugger-selection-popup-on-windows-8-8-1.aspx
Three: A very important thing
I noticed that you said, you are adding db entries in Application_Start. You should keep in mind that, Application_Start does not have a HttpContext, ViewContext, So your db access code may fail for so many others reasons.

Make sure that the Global.asax file is actually deployed to the destination folder in the root. If the file is not present then the code behind you have written for Application_Start will never be called.
Also make sure the signature is correct
public class Global : System.Web.HttpApplication {
protected void Application_Start(object sender, EventArgs e) {/*do something here like logging so you know it was called*/}
}

If you are running Server 2008R2 (or earlier) and/or IIS 7.5, you might want to look into the Application Initialization module. This can be downloaded here:
www.iis.net/downloads/microsoft/application-initialization
With IIS versions prior to 8.0, the application start is not called until the first web request arrives. I'm reading your question as you want your application start to be fired before the first web request, yes?
Here is a fantastic guide to configuring this module (if it applies to you):
https://blogs.msdn.microsoft.com/benjaminperkins/2014/01/07/configure-the-iis-application-initialization-module/
The key takeaways is that you need to set your app pool to 'AlwaysRunning' instead of 'OnDemand'. You also need to set a preloadEnabled flag for your website. Once both of these are done, fire off an iisreset and you should see the results of your application start (look in the database since it's writing there).
Other answers are relevant as well, in that this is tough to debug and you're missing all the niceties you're used to such as a httpcontext in app start.
If you are running IIS 8.0 - you should still read the above link to configure preloading.

This did work for me:
Menu -> Build -> Clean Solution
Menu -> Build -> Rebuild Solution
Then, Application_Start() was fired only for the first time.

In my case in production environment App_global.asax.compiled was missing and all content of global.asax not fired.

A registration already exists for URI after stop/start

I am currently working on an application where I am creating a ServiceHost, then getting rid of it, then recreating it later. The problem is that once I get rid of the service host when I try to recreate it I get the exception "A registration already exists for URI after stop/start." The weird thing is I have three separate hosts and one works and two don't. I assume something is not being disposed of properly but I'm not sure why.
I am creating the hosts like this
host = new ServiceHost(typeof(MyService));
host.Open();
Then getting rid of them like so
if (host != null)
{
host.Close();
host = null;
}
I have also tried abort instead of close without any luck.

Though I am not sure about the exact issue, I can give you a little thought on it and some workaround.
If you are working in Windows 7, any URL you create as part of your hosting has to get registered. Netsh command usually helps us register and unregister the URLs.
For both registering and unregistering URIs you need to have admin permission.
You may try the following.
If you are running your exe, try running it in Administrator mode. (Right click and select admin mode).
If you are trying out with visual studio, try to restart the visual studio in admin mode and run the app.
Try to unregister the URI and try again using Netsh.
http://saravananarumugam.wordpress.com/2011/03/01/http-could-not-register-url/
may help you.

Restart a WCF service hosted by a C# console application

I have a WCF service that is hosted on a c# console application. Is there a way to restart this service, preferably by calling an endpoint in the service itself (ex. myService.Restart()).
Thanks

I have to do something similar when I perform an automatic update of a remote WCF service. In your Restart() method, close the host:
try
{
host.Description.Endpoints.Where(x => !x.Address.ToString().EndsWith("MEX")).ForEach(endpoint => _log.InfoFormat("Closing {0}", endpoint.Address));
host.Close(TimeSpan.FromSeconds(5));
}
catch (Exception)
{
host.Abort();
}
I wait for my update to apply, and then after a success or failure, I re-open the host using the same code I used to start it in the first place.
If you just wanted to restart immediately, you could just call host.Open(), or you could set up a timer to call it, etc.
try
{
host.Open();
host.Description.Endpoints.Where(x => !x.Address.ToString().EndsWith("MEX")).ForEach(endpoint => _log.InfoFormat("Host opened at: {0}", endpoint.Address));
}
catch (Exception ex)
{
_log.Error("Unable to open host.", ex);
}

To answer my question, I have solved the problem by doing the following:
Separating the code that loads the DLL files from the WCF service code into another class library project
Create an interface with the same method signatures as the ones that load DLL files in the new project (this interface is used by both projects now)
In the web service, load the other project in a new application domain. This way the DLL files are locked by the new application domain not the default.
If I want to update my nunit DLL files now, all I have to do is unload the application domain from the web service, update the files and finally create a new application domain.
AppDomain remoteDomain = AppDomain.CreateDomain("New Domain");
IClass1 class1 = (IClass1)remoteDomain.CreateInstanceFromAndUnwrap(
"Test1.dll", "Test1.Class1");
Note: IClass1 is the common interface between the projects.

you definitely are not going to be able to 'restart' a faulted service from calling that same service itself. In theory you could host 2 services in the same process. put the one you want to be 'restartable' in a public static variable and restart it within the other service. The problem would be restarting the restarter service if it faults... :) and you definitely want 'administrator-like' restrictions on your restarter service so unauthorized users can't do it.

It's a bit kludgy, but I suppose you could expose a callback on your service that the host could attach to and take appropriate action when it's triggered. That would give your host the ability to decide what a "restart" really means and how it needs to be executed. More importantly, it lets your decide whether it should do something extreme like spawn off a watcher process and then off itself or gracefully trash and reinstantiate your service (preferable).
Mmmmmm... kludge....

You cannot ask a service to restart itself. Consider a windows service (a service hosted in windows provided container) which has a RESTART functionality. Here RESTART functionality is provided not by the service but by the container. The container controls how to stop the service and start it.
Similarly in your case, you should try to look out for options if your container can provide the functionality you need. Since you want to control it remotely, the container should also be available remotely, which cannot be possible if the container is a console application. Instead it has to be another web service or web application.