Omnisharp-vscode: Error: Cannot start Omnisharp because Mono version >=4.0.1

[aeschli]

_From @blopez2010 on March 29, 2017 5:15_

• VSCode Version: 1.10.2 (1.10.2)
• OS Version: macOS Sierra 10.12.3 (16D32)

Steps to Reproduce:

1. Install latest dotnet core cli.
2. Follow steps on https://docs.microsoft.com/en-us/dotnet/articles/core/tutorials/using-on-macos
3. Go to output and look for following error:

[INFO] Starting OmniSharp at '/Users/blopez/Documents/CODEI/gitrepos/dotNetCore/tutorial/golden/golden.sln'...
[ERROR] Error: Cannot start Omnisharp because Mono version >=4.0.1 is required. See http://go.microsoft.com/fwlink/?linkID=534832#_20001

and this is what I got from vscode dev tools.

shell.ts:426Cannot start Omnisharp because Mono version >=4.0.1 is required. See http://go.microsoft.com/fwlink/?linkID=534832#_20001: Error: Cannot start Omnisharp because Mono version >=4.0.1 is required. See http://go.microsoft.com/fwlink/?linkID=534832#_20001
at /Users/blopez/.vscode/extensions/ms-vscode.omnisharp-0.3.3/out/omnisharpServerLauncher.js:59:24
at process._tickCallback (internal/process/next_tick.js:103:7)

I have downloaded and installed that mono version several times from http://www.mono-project.com/download/#download-mac, close vscode and reopened, restarted my mac and same error message in vscode output.

Does anyone have this error too?

Thanks in advance.

_Copied from original issue: Microsoft/vscode#23517_

[DustinCampbell]

Hi -- it looks like you are using the old legacy OmniSharp extension installed, which is no longer supported. You should uninstall that extension and install the latest C# extension.

[blopez2010]

Thanks Dustin,

Are you talking about this one?

https://marketplace.visualstudio.com/items?itemName=ms-vscode.csharp

If it does, that is the one I'm using though.

Regards,

[DustinCampbell]

The detail you provided above indicates that is not the one being loaded. It's likely that you have both installed:

/Users/blopez/.vscode/extensions/ms-vscode.omnisharp-0.3.3/out/omnisharpServerLauncher.js:59:24

Remove ms-vscode.omnisharp and everything should work fine assuming you have the latest ms-vscode.csharp.

[blopez2010]

Thank you @DustinCampbell I didn't noticed I had the legacy extension installed... sorry to waste your time.

[DustinCampbell]

It wasn't a waste at all. Does that fix the problem for you?

[blopez2010]

Yes it did!! thanks man!

[DustinCampbell]

Excellent. Happy to help.