Exception thrown: The remote certificate is invalid according to the validation procedure

Question

Good day,

I am running an ASP.NET CORE Blazor application in one of my PCs (Windows 10) on Visual Studio 2019 and it is working fine. I opened the same project on another PC (Windows 7) in VS Code and the following exception is thrown.

{System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception.\r\n ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.\r\n   at System.Net.Security.SslStream.StartSendAuthResetSignal(ProtocolToken message, AsyncProtocolRequest asyncRequest, ExceptionDispatchInfo exception)\r\n   at System.Net.Security.SslStream.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)\r\n   at System.Net.Security.SslStream.PartialFrameCallback(AsyncProtocolRequest asyncRequest)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n   at System.Net.Security.SslStream.ThrowIfExceptional()\r\n   at System.Net.Security.SslStream.InternalEndProcessAuthentication(LazyAsyncResult lazyResult)\r\n   at System.Net.Security.SslStream.EndProcessAuthentication(IAsyncResult result)\r\n   at System.Net.Security.SslStream.EndAuthenticateAsClient(IAsyncResult asyncResult)\r\n   at System.Net.Security.SslStream.<>c.<AuthenticateAsClientAsync>b__65_1(IAsyncResult iar)\r\n   at System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n   at System.Net.Http.ConnectHelper.EstablishSslConnectionAsyncCore(Stream stream, SslClientAuthenticationOptions sslOptions, CancellationToken cancellationToken)\r\n   --- End of inner exception stack trace ---\r\n   at System.Net.Http.ConnectHelper.EstablishSslConnectionAsyncCore(Stream stream, SslClientAuthenticationOptions sslOptions, CancellationToken cancellationToken)\r\n   at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean allowHttp2, CancellationToken cancellationToken)\r\n   at System.Net.Http.HttpConnectionPool.CreateHttp11ConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)\r\n   at System.Net.Http.HttpConnectionPool.GetHttpConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)\r\n   at System.Net.Http.HttpConnectionPool.SendWithRetryAsync(HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)\r\n   at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)\r\n   at System.Net.Http.DiagnosticsHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)\r\n   at System.Net.Http.HttpClient.FinishSendAsyncUnbuffered(Task`1 sendTask, HttpRequestMessage request, CancellationTokenSource cts, Boolean disposeCts)\r\n   at System.Net.Http.HttpClient.GetStringAsyncCore(Task`1 getTask)\r\n   at Microsoft.AspNetCore.Components.HttpClientJsonExtensions.GetJsonAsync[T](HttpClient httpClient, String requestUri)\r\n   at Workspace2.Pages.OrdersGrid.OnInitializedAsync() in c:\Users\dell\Desktop\Workspace2\Pages\OrdersGrid.razor:line 49}

Inner exception is null and the error message is: The remote certificate is invalid according to the validation procedure.

I am using .NET CORE SDK 3.1.0 preview 2. Here is the code that throws the exception:

@code{
    public List<ProjectVM> projectsDataSource { set; get; }

    public void ActionComplete(ActionEventArgs<Order> Args) { }

    protected override async Task OnInitializedAsync()
    {
        try
        {
            projectsDataSource = new List<ProjectVM>();
            projectsDataSource = await Http.GetJsonAsync<List<ProjectVM>>("/Api/Default/GetProjectsList");

        }
        catch(Exception e)
        {

        }
    }
}

Please help.

Thanks in advance.

Answer 1

The answer from agua from mars does not take into account that you also have to generate a local certificate for development before you can tell your os to trust it.

You can run the commands in this order, then run your app again.

dotnet dev-certs https --clean
dotnet dev-certs https
dotnet dev-certs https --trust

The command dotnet dev-certs https generates the certificate.

Answer 2

When you run the code using VS 2019, it installs a self-signed certificate on your machine for https redirection. (a message box is displayed informing the certificate installation).

But VS code doesn't do it for you.

Read this doc should help : https://docs.microsoft.com/en-us/aspnet/core/security/enforcing-ssl?view=aspnetcore-3.0&tabs=visual-studio#trust-the-aspnet-core-https-development-certificate-on-windows-and-macos

You can try to run this commands

dotnet dev-certs https --clean
dotnet dev-certs https --trust