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"C# 2017 compiler could not be created" error message while opening project

I've Visual Studio 2017 community edition. I have a C# project created using Visual Studio 2015. When I try to open the project in VS 2017 I get an error message prompt:
--------------------- Microsoft Visual Studio
Project 'dataStructureInCSharp' could not be opened because the Visual C# 2017 compiler could not be created.
Please re-install Visual Studio.
--------------------------- OK
I'm trying to obtain help if anyone else has faced similar issue. I feel going the uninstall and then reinstall route is very costly for me and would try that option last if I've got no other resort.
What I've done so far :
Tried starting visual studio with administrative privileges
But problem remained same.
I tried creating a new console project solution from scratch but in that case I get very same error and an additional error error also shown below:
System Environment: Windows 7 Ultimate Service Pack 1

You can try to close all VS 2017 instances and delete the folder %localappdata%\Microsoft\VisualStudio\15.0_xxxx\ComponentModelCache, then open VS to create a new Console project.
Or
please re-run the VS 2017 installer as administrator, click the icon beside ‘Launch’ button and choose ‘Repair’ to repair as shown below:

Just to brief the history of my problem, I had first installed Visual Studio(VS) 2017 community when it was in RC stage. This was first time when I saw the workload based UI of visual studio installation. Initially I simply chose .Net desktop development workload to get started as I was interested in creating only console applications to get my hands dirty.
Initially it was all working well. One fine day I added all other workloads I was interested in namely Universal Windows Platform Development, Azure Development, ASP.NET and web development,Node.js development, and Mobile development with .Net. I'm not sure if there any of the specific workloads to be blamed for the issue I've posted.
Just to avoid the case if RC and RTM release builds might not have messed up my entire environment, I simply uninstalled the entire stuff, rebooted my machine and installed it again from scratch from latest RTM release for Visual Studio Community.
I would strongly recommend that you first try possible solutions suggested by #Sara-MSFT before doing clean reinstall just in case if it works. It can save you couple of hours required in whole reinstallation process if it works.

Install Monogame on Visual Studio 2017

I am trying to install Monogame on VS 2017 however the option on the installer for VS 2017 is greyed out, even though I have VS 2017 installed. I also have VS 2015 and VS 2010 however I am not sure if it is those that are causing a problem. The version of MonoGame is 3.6.0.1625 and I currently have the directory: C:\Users\MY NAME\Documents\Visual Studio 2017\Templates\ProjectTemplates\Visual C#
Please help thanks

If anyone have this problem and is trying to install on non Admin account then just copy over whole Visual Studio 2017\Templates structure from your Documents to Administrator's Documents. (or the account with admin right you use in UAC prompt to install)
That solved it for me :)

This problem often happens when your templates are in the wrong directory.
The path you provided seems to be the right one tho.
Are your VS2015 templates in the C:\Users\MY NAME\Documents\ directory aswell ?
If not, try to move your VS2017 templates to the same directory as your VS2015 templates.
If those two are both in C:\Users\MY NAME\Documents\, look into Documents\Visual Studio 2017\Templates\ProjectTemplates and try to find the Visual C# folder. If it is missing add a new folder with this name and try again.

OK, simple answer is, that until MonoGame 3.7 drops, you are going to need to download the latest MonoGame Development build from the download page. This is fine as the dev build is still very stable and based off the current MASTER version of MonoGame from source.
I did a short Video on my "Darkside of MonoGame" channel a while back which walks you through everything you need to know to get up and running using VS017. (there is even a version there for VS2015 :D)
https://www.youtube.com/watch?v=zphaylhOrm0
Hope this helps.

I was having this same issue. Uninstalling MonoGame then Visual Studio, and reinstalling Visual Studio then MonoGame worked for me.

How to run asp.net project on localhost:xxxx without Visual studio?

I recently installed DevExpress on my machine, when running it's demos
I found that the it was able to run the project on http://localhost:xxxx.
My question is:
What DevExpress is doing behind the scenes to run a project on localhost without Visual studio?
I found this question, however it only clarifies how can the project "run" manually without Visual Studio. DevExpress is programmatically running the demo project without my manual help.
Any idea? Kind folks?

Consider running the below command
iisexpress /path:c:\myapp\ /port:9090

Issues moving solution from VS2013 to VS2015 having to do with cryptography?

I have a relatively large WinForms application that has been developed under Visual Studio 2013. I recently upgraded to Visual Studio 2015 on another computer and have been trying to get the project working under it.
My first issue/concern is that when I open the project for the first time in Visual Studio 2015 it does not ask me to "upgrade" the solution to Visual Studio 2015, it happily just opens the solution. I am used to having Visual Studio ask to "upgrade" the solution and create a new .sln file that is recognized as a, for example, Visual Studio 2013 solution instead of the old VS10 solution.
The actual issue I am facing is ~10 errors that seem to deal with cryptography. From what I can guess this has to do with the solution itself and what microsoft does with it in the background seeing as the most cryptography I use in the project is generating Guid.
An image of the errors
The one other issue I have is that, as I am not used to, I cannot double click on the errors them self to be lead to where Visual Studio thinks they are occurring. Thus I am not sure what is generating them or where to go from here.
Any suggestions?
This is a Windows 7 installation on an older model Lenovo Thinkpad. I do not have admin privileges on this computer either.
EDIT: So far I have tried to add <enforceFIPSPolicy enabled="false"/> to the file Visual Studio 15 settings at C\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Devenv.exe.config, though whenever I try to edit it (even after a fresh restart) the file is "always" opened by another program. So it seems I cannot edit the file to turn off FIPS for Visual Studio 15.
I am still open to suggestions or clues.
EDIT2: I have managed to get <enforceFIPSPolicy enabled="false"/> into the IDE settings with the help of IT (Using this article). Though this seems to do absolutely nothing, it seems that it is being ignored.
Another issue/clue here is that even if I create a brand new C# project in Visual Studio, when I try to compile I receive the same errors. So I have to assume that Visual Studio is using the SHA256 class somewhere "in the background". If I did have control over its usage I would try to implement #Kevin 's answer below.
I have found another possible solution on the web though I am not sure of its validity
VS 2012 now builds C# projects in a separate process that runs
msbuild. The entry you added to devenv.exe.config (that worked for VS
2010) won't be seen by this process. You should add the same entry,
namely
to the config file for msbuild; typically that's found at
c:\Windows\Microsoft.Net\Framework\v4.0.30319\msbuild.exe.config"
I will try to get this done when I have time for the .NET 4.5+ msbuild.exe.config files and report back.

The solution I went with is outline here.
<enforceFIPSPolicy enabled="false"/> was added to a few files, namely
C:\Program Files (x86)\MSBuild\12.0\Bin\msbuild.exe.config
C:\Windows\Microsoft.Net\Framework\v4.0.30319\msbuild.exe.config
C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Devenv.exe.config
Though I think the one that actually made it work was the first file.

You can't double click on the error and have it go to where the error is being thrown because it is being thrown inside the SHA256 class. If the FIPS compliance bit is set, any non-FIPS compliant .NET cryptography classes throw this error.
You have two choices to fix this...
First, you can just turn off the FIPS compliance bit on the machine where you are trying to run the app (not recommended).
Otherwise, you can update the code to use the FIPS compliant version of SHA256 (SHA256CryptoServiceProvider). This will require .NET Framework 3.5 or greater.

VSP2340 Environment variable issues suddenly when profiling an app

Can anybody explain why i'm suddenly getting this when trying to do any kind of performance profiling (the same way i always have) from within VS2012.
VSP2340: Environment variables were not properly set during profiling run and managed symbols may not resolve. Please use vsperfclrenv before profiling.
I've googled and tried a few things, but i'm unable to find out how to get this working from within VS2012 again.
I found somebody with the same unanswered issue a couple of weeks back here: VS2013: "VSP2340: Environment variables were not properly set" even when running from IDE
Thanks in advance.

I've had the same issue on Visual Studio 2012. Follow the steps below:
Start - All Programs - Microsoft Visual Studio 2012 - Visual Studio Tools
Right click "Open VS2012 x64 Native Tools Command Prompt" and select run as administrator
The command prompt opens. Run vsperfclrenv /globalsampleon
Reboot machine