Error 500.21 when running site on IISExpress using visual studio - c#

I know this question was asked before but I couldn't find a solution that helped me anywhere and feel hopeless.
I'm developing asp.net web sites using iis express.
Recently after accidently messing with visual studio installations I started getting error 500.21 when running any web application through visual studio (I tried running it from all three I have installed - 2013, 2015, 2017). When doing so I get:
error 500.21 - 'Handler "ExtensionlessUrlHandler-Integrated-4.0" has a bad module "ManagedPipelineHandler" in its module list.'
All the projects web.config file has not been changed, it is working for my other team members and has worked for me before, therefore I don't think the problem is there.
Things I've tried to track the issue:
When running sites directly using the IISExpress exe through the cmd, they run perfectly, which makes me think the problem is related to visual studio perhaps, and not related to IISExpress or it's applicationhost.config which seems to be ok.
Countless of reinstall/repair operations on all visual studio/iisexpress/aspnet components I have on my computer without success.
Running the "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe -i" which was mentioned alot when I searched this issue. Not working.

It took me a while to figure out that the applicationhost.config that visual studio references to when running sites on IISExpress was in the .vs folder and not in the IISExpress folder itself.
The file in the .vs folder was corrupted and after replacing it with the applicationhost.config from the IISExpress folder things started working out

Related

Visual Studio "Unable to copy file" during publishing

I keep getting this error during the publishing of my VS 2019 C# win forms project
Unable to copy file "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\PublicAssemblies\Microsoft.VisualStudio.TextManager.Interop.8.0.dll" to "bin\Debug\app.publish\Application Files\Database Client_2_0_0_47\Microsoft.VisualStudio.TextManager.Interop.8.0.dll". Could not find a part of the path 'bin\Debug\app.publish\Application Files\Database Client_2_0_0_47\Microsoft.VisualStudio.TextManager.Interop.8.0.dll'. Database Client
This also happens with 4 other DLL's with some being from VS 2019 itself and some from NuGet packages
This has only started happening recently so I'm unsure whether this is an issue with VS 2019 as no fundamental code has been changed and the only thing that has is some logos on a few .rdlc documents (Microsoft Report Viewer).
I'm running VS 2019 Community on version 16.11.4 with only .Net Desktop development, Office/Sharepoint development and a few individual packages installed.
I've looked around and can only seem to find people having issues with the .exes themselves due to them still being open however this is not the case for me as I have checked and there are no background processes like devenv.
What's strange is both the Debug and Release build fine with no issues whatsoever.
I've also tried deleting the \bin and \obj folders to no avail.
Below are some images of my settings that involve publishing
Publishing Main Settings
Prerequisites
Deployment
It seems the solution to this problem, as #HansPassant commented, was to shorten the build path as it was exceeding the MAX_PATH variable.
Once my project was moved from the default C:\Users\Drew\source\repos\ to just the C:\ drive my project was able to publish successfully.

VSPerf "Instrumention" Tool has stopped working - VS 2017

I had been trying out some of the Performance Profiler tools in VS 2017. All was working great except when I tried the Instrumentation profiling method. It asked to elevate the permissions of that process. Which I did.
Now every time I try to debug my app, I get an error that the VSPerf "Instrumention" Tool has stopped working.
I've tried everything, clearing out my .vs folder, bin folders, looking through the .csproj and .sln files. Completely repairing Visual Studio and removing whatever references I could find to "performance" in the options. It's getting really irritating.
Any suggestions?

Unable to launch the configured Visual Studio development web server

I'm using VS2017 and when I tried to run my app just standard noting extra with IIS express it fails.
Error:
An error occurred launching IIS Express. Unable to launch the configured visual studio development web server. Uncaught exception thrown by method called reflection.
I've set the port to 8080 instead of 56000.
Any ideas how what is wrong? Yes I installed IIS Express but it's not running in the background. I've tried to start VS in Administrtor mode but no luck. I've also deleted the .vs folder and restarted but again no luck.
According to this blog, the following steps should fix the issue:
close all Visual Studio instances
go to your ASP.NET project/solution folder, delete “.vs” hidden folder
click “Start”, search IISExpress, go to IISExpress folder, go upper level and delete whole IISExpress folder
start Visual Studio with Administrator privilege
create a fresh new ASP.NET project
run this project, this time you should see IIS Express is launched by Visual Studio correctly
close this solution but not close Visual Studio, open the ASP.NET project which you have problem with, and run it now, you should see IIS Express is launched correctly

Data area passed to a system is too small error in UWP app

My UWP app is building,rebuilding and deploying fine but it is not running.
Although, it works fine in other system.
I am using Visual Studio professional 2015 since 5 month to build this project and all of a sudden it has started showing this.
When i try to uninstall the app it doesn't give any option to uninstall also.
I have tried restarting the system and cleaning,rebuilding the project file but nothing seems to work.
Thanks in advance.
Causes:
It is a known issue in Visual Studio 2015.
For more info: unable to activate Windows Store app
Solution:
Update to Visual Studio 2017
For other solutions:
Unable to activate windows store app the app didn't start
Unable to activate Windows Store app: The App1.exe process started, but the activation request failed with error ‘The app didn’t start’
It seems like the directory or the folder were corrupted so that is why every time when i was running the application it was installing in a non packaged version therefore i was not getting the option to uninstall it properly.
I tried by deleting the whole folder which created in AppData folder of the Users but it didn't work.
So finally i created a new folder and moved my solution over there.And everything is working pretty much fine now.I thought we could solve this problem by repairing Visual Studio but since this issue is not related with Visual Studio and moreover it takes half of your day to repair Visual Studio so only moving the project to a newly created folder would be a good idea in this case.

Error reported in web.config, but only when it is not open in the editor in Visual Studio Community 2015

I just changed to Visual Studio Community 2015 and I'm having a weird issue running a project. The project builds without any errors. But, when I go to start debugging I get the following error:
There is an error in web.config. Please correct before proceeding. (You might rename the current web.config and add a new one.)
This only happens if web.config is not open in the editor in Visual Studio. If I open web.config in Visual Studio and try to run the project, I am able to do so and no errors are reported.
Has anyone suggested that we close and reopen Visual Studio?
I had the same problem in a Web API project in VS Enterprise 2015. I knew there was nothing wrong with the Web.config file because, like you, all I had to do was to have it open before hitting F5. It went away after I removed and re-added the project to the solution during solution re-organizing. You might want to try that. No logics here but then the error seems illogical too.
I fixed/stopped the issue above and wanted to communicate what my fix was with the exact same symptoms as above. I had switched to a different published environment when this started happening (from UAT to Dev) and I commented out a section in the web.config file. Double checked to make sure I commented out the exact text. I even cleaned my solution and rebuilt it, same problem. Strangely, I could publish to the dev environment and the application would run (Web app with IIS 7).
The only difference between my local environment from when it was working and this problem was my web.config file. So I was thinking VS was having trouble accessing the file when not open in the IDE. I checked properties and the file had the appropriate settings. I then checked in the solution into our source code repository and the issue went away. We implement an SVN solution here.
Hope this helps.

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