Visual Studio and C# scripts no longer opening!

I have the same problem sometimes. The preferences are set on VS.

When I restart Unity, the problem is solved, most of the times.
Let's hope that this problem is fixed in the new Unity .

 

Got the same issue now. It doesn't solve by restarting Unity and neither by resetting the file associations in VS.
I got 2 editions of VS installed:
The Express VS 10 starts if I select it. I don't know if Unity found it itself.
Unity didn't know about the pro version so I used the Preferences -> Browse option to select the specific VS exe to start. It starts MD instead.

For some reason, this now works again. I installed a plugin to VS and switched between all options and at some point Unity opened the right VS again. No idea what happened.

 

What you can do, is work the other way:
Start your VC.
Go to: File --> Open --> Project/Solution
select the csharp solution from your Unity project.

Keep VC running. If you create a new script, your VC will ask for a reload, but you can always program within the program.
This is the way I work now and I like it.

 

i know this thread is somewhat dated but i post anyway, because i found a solution or better said the reason of such strange behavior

OS: Win 7 Ultimate

it fixed for me when i turned Visual studio back to NOT start as Administrator wich i turned on before for some reason

in short: it looks like Unity 3d behaves somewhat strange if the external editor is started as Administrator i am not sure what is the deeper reason of that behave, i could think of this: unity 3d isnt started as Administrator so it cant start another programm that should be started as Administrator.

how ever: make sure Visual Studio is NOT started in Administrator mode should fix it!

have a nice day....

 

Hi guys,
I have found a solution to be able to kind of work this problem out.
It seems there is a problem with the opening of visual studio and the sln file.
So all you have to do is open the file yourProject-csharp.sln not yourProjet.sln (those 2 files are automatically generated by unity) and then you can have all your interactions back between Unity and Vs.
Hope this can help you out

 

Changing the "start with administrative privilege" option woked for me, thx

however; instead of opening both without admin, I open both WITH admin. It seems installing a new version of unity resets this setting (makes a new shortcut without it).

 

i just downloaded unity and tried to open a c# project but it never opened and they told me to check external appliction preferences

 

Hi guys,
I removed *.sln file and restart Unity. The problem is solved.

 

That didn't work for me... scripts still won't open.

 

I have same problem

 

I had the same problem with Visual Studio Code and none of the solutions above helped me. I uninstalled Visual Studio Code and then reinstalled it, but this time using the system installer rather than the user installer.
I think it might have been an update to Visual Studio Code that broke it.

Answer: Reinstall Visual Studio Code

 

Simply delete
.vs folder
.vscode folder
and
all 3 assembly files
including .sln and restart unity everything becomes normal

 

Where do you find theses folders?

 

In your project. They may be hidden by the system, so in some cases, you may have to show hidden files/folders.

 

Unity 2019 - 2020 So/ I had a problem with Unity hub - new Unity versions isn't intaling at all (Incomplete or corrupted file)
and as bonus in Unity my Visual studio doesnt have proper intellisense
If you have simple only last problem :
1. preference - external tool - script editor - Visual studio
But in this case my Unity stop to open scripts.
Than I found onlyone total solution:
1. delete Unity
2 Instal Unity hub
3. Instal Visual Studio from microsoft separeted
4. Download torrent (dont't forget to turn off Mac version) from arhive on unity site https://unity3d.com/ru/get-unity/download/archive
5. Instal Unity and all modules separeted! Not from Unity hub! Only by hands as true old-school
6. Locate from hub installed Unity version
Done! You are awesome! everything work!
Hope it will help? becose I didn't found any solution online for those kind of problem

 

Hello all.. Unity and VS2019 was working ok till a day ago. Unity coding no longer opens in VS2019 C#. So now I'm reinstalling VS2019 AND Unity to see if this will fix this...

 

Also was working on Unity High Speed Chase training when the crash happen and it no longer opened code in VS from Unity. What I was doing up to that point was do a step and save it as a VS program with basically the same title description shortened. Was working well up to then.