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Send mail via System.Net.Mail.SmtpClient isn't working on Android, but on Windows

See original GitHub issue

Description

I’ve created a small sample trying to send an email using theSystem.Net.Mail.SmtpClient. The sample is working on Windows, but not on Android. An Interop+AndroidCrypto+SslException is thrown.

Steps to Reproduce

Create a File > New .NET MAUI App
Create a System.Net.Mail.SmtpClient and calling the SendMailAsync() on Android
An Interop+AndroidCrypto+SslException is thrown
Run the same code on Windows and the email is sent

I’ve tried using an outlook.com mail address with the smtp-mail.outlook.com host.

See the following basic sample: MauiSendMailSample.zip

Version with bug

6.0.486 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android, I was not able test on other platforms

Affected platform versions

Android

Did you find any workaround?

No response

Relevant log output

{System.Net.Mail.SmtpException: Failure sending mail.
 ---> System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception.
 ---> Interop+AndroidCrypto+SslException: Exception of type 'Interop+AndroidCrypto+SslException' was thrown.
   --- End of inner exception stack trace ---
   at System.Net.Security.SslStream.<ForceAuthenticationAsync>d__175`1[[System.Net.Security.AsyncReadWriteAdapter, System.Net.Security, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]].MoveNext()
   at System.Threading.Tasks.TaskToApm.End(IAsyncResult asyncResult)
   at System.Net.Security.SslStream.EndAuthenticateAsClient(IAsyncResult asyncResult)
   at System.Net.TlsStream.EndAuthenticateAsClient(IAsyncResult asyncResult)
   at System.Net.Mail.SmtpConnection.ConnectAndHandshakeAsyncResult.TlsStreamAuthenticateCallback(IAsyncResult result)
--- End of stack trace from previous location ---
   at System.Net.Mail.SmtpConnection.ConnectAndHandshakeAsyncResult.End(IAsyncResult result)
   at System.Net.Mail.SmtpConnection.EndGetConnection(IAsyncResult result)
   at System.Net.Mail.SmtpTransport.EndGetConnection(IAsyncResult result)
   at System.Net.Mail.SmtpClient.ConnectCallback(IAsyncResult result)
   --- End of inner exception stack trace ---
   at MauiSendMailSample.MainPage.OnMailButtonClicked(Object sender, EventArgs e) in MauiSendMailSample\MauiSendMailSample\MainPage.xaml.cs:line 36}