ASP.NET MVC5/IIS Express unable to debug - Code No

Question

I start a VS2013 VB.Net MVC5 Web Application, set a breakpoint in HomeController About method and run "Start Debugging", navigate to About page and receive the message "Code not running - The current Thread is not currently running or the call stack could not be obtained" preventing any debugging.

If I set a breakpoint in Global.asax Application_Start, the breakpoint works fine. Changing the "Enable Edit & Continue" makes no difference.

Anyone have any ideas what is happening?

Update: My environment was Windows 8.0 Pro with VS2013 Ultimate.

I have since flushed my system and done a completely fresh install of Windows 8.1 Pro, VS2010 Ultimate, VS2012 Ultimate, & VS2013 Ultimate.

Same test done on all 3 versions of VS - File > New Project > MVC (Default). All 3 versions of VS are reporting "Process with an Id of xxx is not running."

VS2013 debug trace reports "The program '[7720] iisexpress.exe: Program Trace' has exited with code 0 (0x0). The program '[xxxx] iisexpress.exe' has exited with code -1073741816 (0xc0000008) 'An invalid handle was specified'."

I have run VS in and out of Administrator mode and receive the same results. I have uninstalled and reinstalled IIS Express 8.0.

Answer 1

I had a similar problem while moving from Visual Studio 2013 to Visual Studio 2015 on a MVC project.

Deleting the whole .vs solution worked as a charm as Johan J v Rensburg pointed out.

Answer 2

Go to project directory .vs/config/ and remove applicationhost.config . Then restart project.

Answer 3

None of the above answers worked for me but I finally found what my issue was. Hopefully this will help someone down the line.

First run IIS Express from command prompt to validate that the site can or cannot be run

https://docs.microsoft.com/en-us/iis/extensions/using-iis-express/running-iis-express-from-the-command-line

Im my case, i got an error saying that C:\Windows\Microsoft.NET\Framework64\v4.0.30319\CONFIG\web.config had malformed xml on line 14. Looking at that line in the file it just said null null null null null etc.

The fix for me was to replace the web.config file with one from my coworkers. IMPORTANT you must get the file from someone running the same version ie if you are VS2015 get a copy from someone running VS2015. If you get it from someone running a different version you will see an error saying it could not load an assembly from the manifest.

Hopefully this helps someone that has tried all the suggestions above. I think the cause of this for me was updating from trial mode and adding a product key within VS2017

Answer 4

Delete File C:\Users\congt\Documents\IISExpress

Answer 5

I started to get this problem with Asp.Net Core Web Applications in Visual Studio 2017. It didn't matter if it was the .Net Core Standard version with .Net 4.5.2 or the Core version with 1.1 in my case. IISExpress crashed when I started debug.

Tried everything, nothing worked until I went into add/remove programs in Windows 10 and I uninstalled .net core 1.0 runtime (I had both 1.0 installed AND 1.1). Once that was uninstalled, I started Visual Studio 2017 and my .Net Core Web applications (both kinds) and they both started working again!

Answer 6

The solution to the above problem was a simple one. Close down dev environments, go to Documents folder and rename IISExpress. Now set environment variable _CSRUN_DISABLE_WORKAROUNDS ( ref: http://gauravmantri.com/2013/02/05/workaround-for-iis-express-crashing-when-running-windows-azure-cloud-service-web-role-with-multiple-instances-in-windows-azure-sdk-1-8-compute-emulator/ ).

Now reboot PC, start VS, load website and run in debug. IIS automatically regenerated the IISExpress folder and the environment variable resolved conflicts.