I'm making a chat program in Visual Basic. It's supposed to be for LAN, and it's called LANChat.
It starts a listener on port 65535 (just for now) and continues to listen on that port. However, if you tried to open two instances of it at once, there'd be a runtime error. I've handled that, and it shows a MessageBox and closes the program if it detects that the port is currently being used. However, in Visual Studio, when attempting to test the program, it runs the program as if it's already being run. I looked in task manager and I see "LANChat.vshost" is running at the time. Any ideas? The only idea I have is to comment out the exception handling code while testing.
Under your project properties > Debug you can deselect the 'Enable the Visual Studio hosting process'. This will take the hosting process out of the question, if it works then then hosting process was interfering somehow, if not then the problem lies elsewhere.
It would be better to create your progra as a single Instance program. Than you should avoid the vshost probme.
I've done it for myself and it works fine.
Sorry i cannot provide code, I am at home :(
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I'm using Visual Studio 2022 with the React template on .NET (core) 6.
When I press f5 to start debugging, it starts a command prompt to start the development proxy server, fires up my deafult browser (chrome), and everything seems to work OK.
However, about every 2 minutes after, regardless of whether I have touched VS or the app, it then starts another copy of the development server, which then gets stuck with a prompt saying Something is already running on port 3000. Left to its own devices it just keeps starting more.
This doesn't stop the previous one working but it's frustrating to have all these windows appearing, especially as they steal focus when prompting with the "port in use".
Something that I suspect is related is a message appearing in the debug output around every 8 seconds saying "Microsoft.AspNetCore.SpaProxy.SpaProxyMiddleware: Information: SPA proxy is not ready. Returning temporary landing page." However as noted above the SPA proxy certainly seems to be running OK.
Has anyone got any ideas what might be happening or any workaround for this?
OK I managed to figure this out by creating another blank project and comparing them.
The port that the development server will listen on is stored in a file called ClientApp\.env.development; the port that visual studio expects it to listen on is in the .csproj file under PropertyGroup/SpaProxyServerUrl. If there is a mismatch you will get this behaviour because VS thinks the server isn't running and keeps on trying to start it.
In my case I had added the .env.development file to the version control ignore list thinking it wasn't important. This was causing the dev server to listen on the default port 3000.
Apologies, this may not be a good question.
I have a VB based UI application running, supported by C++ modules through COM.
a month before it started to close randomly without any clue. I initially analyzed in perspective of a application crash and expected to see Dumps and Application/System event log entries. I have prior experience in application crash debugging. tried registry configurations (Like, CorporarteWerServer for application hang, LocalDumps and all that).
But no luck.
End user says they don't see any popup like "This application is not responding with options close/wait". The application just closes down without any prompts.
We have logging enabled where we intentionally close the application using exit(). So it is not closing formally.
User does not have testing environment where we can install debugging tools and monitor.
I have verified for insufficient memory and antivirus software and they are fine.
So, Is there any cases where an application can just simply close/crash without any prompts, logs, dumps ?
Please suggest if I am missing something. Also, is there any built-in windows tools to monitor ?
Forgive me if this is a stupid question, I'm fairly new to writing services. I've written a service that runs a timer and the timer code runs some checks to ensure our systems are up and running. It's written in VB.Net, framework 1.1. I then install the service using "sc create". The service works beautifully on the XP Pro machine that I'm developing on. However, when I install the service on a Windows 2003 server 64 bit, the service fails with error 1053 immediately. I put some debugging in to write to a text file as the first line of code in the OnStart function but even that doesn't run, so there must be a problem in the program starting up. Finally in desperation I created a brand new Windows Service in a new VB project in Visual Studio 2003 and compiled an empty service that merely declares and sets the value of a string variable in the OnStart function as follows:
Dim strTmp As String
strTmp = "hello"
Even that failed on the W2K3 server, but works fine on the XP dev machine.
The server has .Net Framework 1.1 installed and working, we use it in our CMS (written in ASP.Net 1.1).
The service runs as the local system account. I tried enabling interaction with the desktop but that didn't help. I ran Process Monitor and there are no access denied events. I emptied the Application Event Log, still doesn't work. No other events to help me out in the logs. Definitely using the Release build of the application. Permissions on the exe file are full control for System and for Admins.
Any ideas anyone? It must be something simple, but I'm damned if I can figure it out!
Thanks in advance.
#DavidHi, many thanks for the suggestions. I don´t think the first point is my problem, partly because the MS article is about stopping or pausing the service, mine fails on starting; but also because the service does not timeout, there is no 30 second wait, it fails immediately. Secondly, when you say add an exception handler to the service startup, do you mean the OnStart sub? I tried adding a debug file write in there, but I'll try adding an event log instead. Regarding the systems checks, it can't be that because the brand new empty test service I created shows the same behaviour and that does not do anything at all. You last point could be the key. My dev environment IS 32bit. I'll do some research on the corflags thing, or perhaps I can build a 64bit dev environment. Many thanks again, you've given me some new things to think about at least!
Ok, have found a workaround. I was putting my exe file in System32. When I put it in a different folder, created by myself, the service ran, albeit briefly. I then had to move the ini file and the log files that it reads/writes to that folder too, rather than System32, and all seems to work nicely. God knows why it doesn't like running from System32 but at least it works now! Thanks for the help guys.
This looks very similar to this question which might help you out:
Starting a windows service fails with error 1053
A couple of other things to look out for:
Make sure you don't have either of the following statements in your deployed service:
System.Diagnostics.Debugger.Launch
System.Diagnostics.Debugger.Break
You may need to run the service with an account other than Local System (depending upon the permissions required by your service).
The 1053 error is a timeout related to the service control manager waiting for the service to respond to your start request. There is a knowledgebase article that refers to managed service stop request issues specifically relating to Framework 1.1-based services, so it is not precisely describing your problem, but it may have relevance in your situation. The link is provided for your reference.
http://support.microsoft.com/kb/839174
The other suggestion I would make to further diagnose the issue is to determine whether the Start is failing due to a "hidden" exception occurring in your service's startup code; the start call would not see the exception and could make you think it was merely timing out.
I would suggest you add an exception handler to your service startup that does nothing more than log a message to the event log with the particulars of the exception if one is caught. That would at least give you an idea that something is going wrong specifically within the service, and give you more information than you have right now.
One last thought: Does the service check the systems you describe over a network connection? If so, LocalSystem won't have sufficient privileges to perform network access.
Good luck!
EDIT One other possibility:
Is your development environment/execuable 32-bit? You mention your server is 64-bit, so you may need to use the "corflags" tool that forces 32bit operation on your executable
corflags /32bit+ YourServiceExectubable.exe
The source for this information was the following SO post:
32-bit Windows services in 64-bit environment
**Unfortunately, it appears corflags is applicable only for 2.0 assemblies, and was designed for specifically this type of problem. **
I finally got my localhost to display the site locally. Everything seems to be working on that end. My next step is to actually be able to step into the code from the VB6 IDE when the web site uses a function from the ActiveX.dll
UPDATE:
I updated the code and removed the issue I was having compiling the code.
Now when I try to debug the site won't open. It just hangs. I'm wondering are there any tutorials that I can read so figure out how to properly get this application setup for debugging?
UPDATE #2
Just to clarify, I got the web site (which references the ActiveX .dlls) locally on IIS 7.5. My hope is that when I open the site (on localhost) I can step through the .dll code at the same time.
That is really what I'm asking.
It's actually quite easy. First of all, do an iisreset. Then load up Visual Basic with your ActiveX DLL. Place your breakpoint, then Run your project.
Then hit your page containing a call to the ActiveX DLL and it should stop on a breakpoint you just set.
With Visual stuido 2010, it's simple to set up SL4 to debug with an out-of-browser installed app. I followed the instructions from here and everything seems to set up fine. Debugging from the browser runs the program just fine, but running from the OOB program gives a different result. After starting, the screen will go blank and then hang forever. I have some concerns that it might be because of some of the technologies that we're using.
Firstly, there's a popup that happens because we're using WCF RIA Services (formerly .NET RIA Services).
"RIA Services will fail unless the silverlight project is hosted and launched from the same web project that contains the RIA Services."
This seems to just be a warning, but I have a suspicion that this warning might be telling me that RIA Services needs to have the .web project as its startup project.
We're also using prism and the error has an odor of a Prism error too. (something loading and then not ever appearing)
Has anyone else had any issues with OOB debugging in SL4? Is anyone else OOB debugging in SL4?
Sorry it's so vague. It's a complicated mess. The only message I see is the italicized popup warning. Then the window (which was previously showing the background of our application) just goes blank
There is currently a known issue with debugging an Out of Browser Silverlight 4 application when using F5 to launch the application from within VS 2010. The question I have is whether or not the application launches without debugging (-F5 or running it from the shortcut)? In the case of using F5, a dialog typically appears with the following error dialog “Unable to start debugging. A fatal error occured. For more details, please see the Microsoft Help and Support web site. HRESULT=0x80070018” and then the application appears to hang. In this case detaching allows the process to continue and then reattaching should allow you to debug the process.
If this is completely blocking or you’re trying to debug code running at startup (like the page startup event), one possible way to get around this would be to put in a call to System.Diagnostics.Debugger.Break, start the program and then attach when dialog pops.
This can be caused by the OOBA install being older than the version you are trying to debug. Remember, Silverlight OOBAs do not automatically update themselves to the latest version of the XAP file that may be available on the server. You have to update them yourself. If you get this error and you have included the auto-update logic in your app, just bounce out of VS, run the app so it auto-updates, then go back in and debug.
Alternately, you can uninstall the app and re-install it. That will ensure you are debugging against the latest VS build.
I ran into this same issue with VS 2008 and Silverlight 3. If I got it, I just jumped out and updated the app then re-ran it in VS and had full debugging.