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Debugger Not Installed While Starting C# Console App in Visual Studio Community 2017

I have freshly installed Visual Studio Community 2017. I have a simple console app that prints a message. When I click the Start button I get the message
Error while trying to run project: Unable to start program
The debugger is not properly installed. Run setup to install or repair the debugger.
If I click on Debug in the menu and Start Without Debugging, I see the output of the program, so build and run seem to be working. However, I guess the debugger is not installed and I'm not sure how to install it. I've done exhaustive Google searches and seen posts talking about running regsvr32 and repair, both of which have proved fruitless.
EDIT:
Installing VS2015 fixed the problem.

#David Bradford, long time after Novell isn't it? Anyway, after looking all over the place this is the best solution I found. You don't have to install VS2015 just follow the directions below. I tried this and it fixed the problem for me and another person I was working with.
Link to the VS developer community that has various comments and the fix below
Added a solution by Andrey · Jun 23 at 06:01 PM
Best Solultion
C:\Program Files (x86)\Common Files\Microsoft Shared\VS7Debug
C:\Program Files\Common Files\microsoft shared\VS7Debug
Solution for this problem for Visual Studio 2017 Community.
Clean folders: Delete all the files in the two folders
C:\Program Files (x86)\Common Files\Microsoft Shared\VS7Debug
C:\Program Files\Common Files\microsoft shared\VS7Debug
Then run repair Visual Studio by clicking the menu (three lines stacked up) to the right of the Modify and Launch buttons.
P.S. This issue happen because dlls corrupted. Here is this case
shareimprove this answer
This seems to be a known issue and is under investigation by the VS 2017 team. More information here: https://developercommunity.visualstudio.com/content/problem/26630/the-debugger-is-not-properly-installed-cannot-debu.html

Unity solution not compatible with visual studio

Since updating to the most recent version of Unity 5.4.0f3, whenever I doubleclick on a script, it launches both Visual Studio and Monodevelop, but I get an error saying that the this version of VS (Community 2015) is unable to open my project. Monodevelop displays it's own, somewhat less clear error message. Please see the screen shots below.
I can still manually open my script using Visual Studio's file menu, but the intellisense code completion no longer works. Anyone know how to fix this? I have Visual Studio's Tools for Unity installed.

I was having similar issues when doing a clean download of an existing Unity project onto a fresh install of Visual Studio Community 2019.
In the end the issue for me was that, although the correct version of VS Tools for Unity was installed, it was 'Disabled' by default in VS's Manage Extensions dialog (Extensions -> Manage Extensions). Just had to click 'Enable', restart Visual Studio, and all worked as expected again.

Turns out it was an issue with my existing install of Visual Studio Tools for Unity (VSTU).
I found a thread where users had experienced similar problems due to an unsupported version of VSTU running on Unity5.2 and beyond. Unity 5.2+ requires VSTU 2.1 or later for VS to work correctly with Unity, more information for anyone interested is available in the documentation here.
I had VSTU 2.3 installed, but removing and reinstalling VSTU resolved the issue, so there must have been a problem with my install. If anyone else has this or a similar issue you can download the latest installer for VSTU here. Thanks to all who chimed in your responses helped me look in the right place!

Please try following steps:
Delete old *.csproj and *.sln files on project's root folder
Check "Edit > Preferences > External Tools" and make sure you've selected "Visual Studio"
Re-open solution by "Assets > Open C# Project" menu

For me it was enough to right click the solution in Solution Explorer and run "Resolve errors".

I will complete what is said above. I experienced this issue today and it took me a while. In my case it was relative to a new install of the Unity Editor.
For some unknown reason the unity tool used on VS (intellisense) was uninstalled. I had to reinstall this : open Visual Studio Installer, select your project and reach the Gaming section where reside the tool for Unity.

The extension "Visual Studio 2019 Tools for Unity" seems no longer available for download via the extension manager. Luckily I recalled that I saw some game development features in the Visual Studio installer, so I picked that one:
It works for VS 2019 (16.11.11) and VS 2022 (17.2.0 Preview 1).

Visual Studio 2013 reporting erroneous "does not contain a definition for" error for recent extension methods

Visual Studio 2013 (vs) compiles a solution fine when manually building (i.e., it reports "Build succeeded", there are no errors in the error list, and running a program shows the latest changes). However, when vs starts building in the background (for Intellisense?), then errors start to come up for recently added extension methods. The extension methods are underlined in red, and right-clicking on them to "go to definition" results in an error that says "Cannot navigate to [method name]".
Extension methods that were created (in the same classes as the methods listed in the erroneous error messages) previous to when this started happening do not show up in the error messages.
I have done a build clean, to no avail.
I do not have resharper installed.
How do I reset the intelisense cache in Visual Studio 2013? I see instructions for Visual Studio 2008, but not for Visual Studio 2013.

For Visual Studio 2015, my solution didn't have an .sdf file, and restarting didn't help. However, the following steps fixed my problem:
Close Visual Studio (important)
Go to [solution folder]\.vs\[solution name]\v14
Delete the .suo file
Start Visual Studio

It turns out that closing all open files, then shutting down Visual Studio, and restarting fixed the issue. pff!

I had a similar problem that I resolved by deleting *.sdf file in the solution directory. VS2013 will re-create it.
UPDATE This is what I know now: https://stackoverflow.com/a/38708050/90475

After testing all above mentioned solutions simply clean and build worked for me.

In VS2010, the only thing that worked for me was removing and adding the reference again.

Very old question, but it happened to me also with VS2019. I have multiple projects in my solution: right-click on the project -> "Unload Project" for each one, and then reload them. This worked for me.
Clean + Build, or
Close all the files + restart VS + clean
Those didn't work (for me).

Visual Studio won't load my VSIX package

I'm trying to create my own VSIX package using the Project template. But when I actually launch it, it doesn't appear to be loading anything. That is, when running the project, it opens up another copy of visual studio, but it doesn't actually load up my plugin. I've compared my plugin to the other sample templates, and I just don't see anything wrong. It seems like it should be pretty straightforward. Are there any other steps besides creating the project that I have to do?

Are you using the visual studio experimental instance for debugging? You can enable this in the Project properties (right click your project and choose properties). Go to the 'Debug' tab and add the following line to 'Command line arguments': /rootsuffix Exp
More information about the experimental instance can be found on msdn.

I spent an entire day trying to reset Visual Studio (2015 Community Edition) by unloading features, deleting the cache directory, using the install to repair -- all with no success.
I finally uninstalled Visual Studio with success. When I initially installed Visual Studio, I had packages errors, like Python, that failed to load, but my Test Explorer worked beautifully. The test Explorer package stopped working in time. After re-installation, everything worked without any package load errors. Also, pay attention to the xml error files, because mine produced exceptions thrown by the package. (The xml error file is reported in the error dialog when Visual Studio informs the package failed to load.

When creating a WCF project in VS2010, I get "Error : WcfProject.csproj cannot be opened. The project type is not supported by this installation"

hey there. So, we have a VS2010 project and the VisualSVN server on one machine. We added a new machine with the client visual svn and the projected loaded in. except for the WCF service. i'm getting a...
" error : the project file c:/..../wcfProject.csproj cannot be opened.
The project type is not supported by this installation."
i've checked the directory, the files and file structure are there and the same as the main development machine. any tips/solutions?
thanks
David K.

I had a similar problem with some WCF solution which I downloaded from a blog.
The solutions of running deveng with the switches did not resolve my issues. After some more searching it turned out that the following clue in the answer of Ralph Willgoss lead to the solution of my problem:
I resolved it by installing the Visual Web Developer.
I also had to (manually) install the Web Platform Installer to (automatically) download the last requirements for the project to properly load.

I had a similar problem when trying to create a new project of the following types:
WCF Service Application
WCF Work Flow Service Application
Syndication Service Library
I was using Windows 7 Ultimate 64bit, with no other versions of Visual Studio installed.
I also had tried many other options, such as:
devenv /resetsettings
devenv /resetskippkgs
ensuring I had C++ option of VS2010 installed
VS2010 Service Pack 1
I resolved it by installing the Visual Web Developer.

There are a few things this could be so I can't give you one specific answer. However, here are a few things to try on your machine that is throwing the error:
First, verify which version of Visual Studio is set as the default for opening csproj files. It could be that you installed SQL or something else that uses an older version of Visual Studio. Sometimes that can give an error. Even if the default is the Visual Studio version selector I've seen it throw an error. Open up the correct version of Visual Studio (through the Programs menu) and then inside Visual Studio try to open the package. If that works, you know the issue is with which version is opening the file.
If that doesn't work, you could try resetting the Visual Studio settings. From the run menu type devenv /setup This should reset the Visual Studio environment and hopefully it will fix the issue. If this does not work, try running devenv /ResetSkipPkgs from the Run menu. This will try to load any packages that Visual Studio previously skipped.
If these steps don't work, let us know. Give us any further error messages that come up after attempting these steps.