TLS broken : vstest.console.exe still use .NET 4.5

[tbolon]

Description

vstest.console project still target net4.5, beside the fact that it's not supported anymore since 2015.

It adds a problem: by default, .net apps build against .net version 4.5 do not use TLS 1.2, so if tests are using HTTP requests to call a server where only TLS 1.2+ is enabled (as per global recommendation) the test will fail.

My reproduction case happens when using Azure DevOps and using vstest task.

Steps to reproduce

• Create a unit tests which requests an http resource only accessible through TLS 1.2
• Run the test using any test host (dotnet test, etc.), the test will pass
• Run the test using vstest.console.exe: the test will fail

-------- System.IO.IOException : Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.
------------ System.Net.Sockets.SocketException : An existing connection was forcibly closed by the remote host

Expected behavior

The request should succeed using the most recent TLS protocol available

Actual behavior

The request fail.

Suggestion

You should at least update vstest.console.exe to 4.7.1+

[tbolon]

It seems that #3646 will fix this problem,

[nohwnd]

I just closed this one this morning because it never got merged and we never had another report of a related issue. #2472

Now we have one again :D

[nohwnd]

Still we will fix by moving to .net462 in next sprint.

[tbolon]

I was just coming back to suggest adding at least the correct AppContextSwitch ;Switch.System.Net.DontEnableSystemDefaultTlsVersions=false. It seems you were quicker :)

[nloyolag]

Just wanted to jump into this thread to report that we are facing the same issue in our Azure DevOps build pipeline. Looking forward to the fix :)

[Evangelink]

Fixed by #3646