我得到这个错误:

根据验证过程,远端证书无效。

每当我试图在我的c#代码中使用Gmail的SMTP服务器发送电子邮件时。 有人能给我指出解决这个问题的正确方向吗?

下面是堆栈跟踪…

at System.Net.Security.SslState.StartSendAuthResetSignal(ProtocolToken message, AsyncProtocolRequest asyncRequest, Exception exception)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessReceivedBlob(Byte[] buffer, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult)
at System.Net.TlsStream.CallProcessAuthentication(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Net.TlsStream.ProcessAuthentication(LazyAsyncResult result)
at System.Net.TlsStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at System.Net.PooledStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at System.Net.Mail.SmtpConnection.Flush()
at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)
at System.Net.Mail.SmtpClient.GetConnection()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at BulkEmail.frmemail.mailsending(String toaddress, String fromaddress, String fromname, String subject, String pwd, String attachements, String mailmessage, String htmlmessage, Int32 i, Int32 j, String replytoaddress)

当前回答

您可以通过在证书无效时询问用户是否想继续来改进代码。你想继续吗?如下:

ServicePointManager.ServerCertificateValidationCallback = 
    new RemoteCertificateValidationCallback(ValidateServerCertificate);

并添加一个这样的方法:

public static bool ValidateServerCertificate(object sender,X509Certificate certificate,X509Chain chain,SslPolicyErrors sslPolicyErrors)
{
    if (sslPolicyErrors == SslPolicyErrors.None)
        return true;
    else
    {
        if (System.Windows.Forms.MessageBox.Show("The server certificate is not valid.\nAccept?", "Certificate Validation", System.Windows.Forms.MessageBoxButtons.YesNo, System.Windows.Forms.MessageBoxIcon.Question) == System.Windows.Forms.DialogResult.Yes)
            return true;
        else
            return false;
    }
}

其他回答

我的问题是在Windows 2003服务器,当调用AuthenticateAsClient。上面的解决方案(例如绕过ServicePointManager.ServerCertificateValidationCallback)不起作用。

原来这是Windows 2003中的一个bug,并且有一个热修复:

"使用加密API的应用程序无法在Windows Server 2003中验证X.509证书"

https://support.microsoft.com/en-us/kb/938397

安装此修复程序解决了我的问题。

还没有人指出明显的,如果你想安全地调试SSL问题,那么总是使用这种方法:

#if DEBUG
    ServicePointManager.ServerCertificateValidationCallback += (sender, cert, chain, sslPolicyErrors) => true;
#endif

即使您不小心提交了代码,它也不会在发布模式下编译。

有一篇MSDN博客文章是关于调查这类问题的:

故障排除ASP。NET -根据验证过程,远程证书无效: http://blogs.msdn.com/b/jpsanders/archive/2009/09/16/troubleshooting-asp-net-the-remote-certificate-is-invalid-according-to-the-validation-procedure.aspx

这里的链接解决了我的问题。

http://brainof-dave.blogspot.com.au/2008/08/remote-certificate-is-invalid-according.html

我去到web服务的url(在有问题的服务器上),点击IE中的小安全图标,弹出证书。然后,我单击Details选项卡,单击Copy To File按钮,这允许我将证书导出为.cer文件。在本地获得证书后,我就可以使用下面的说明将其导入服务器上的证书存储区。

开始一个新的MMC。 文件——>添加/删除管理单元… 单击Add…… 选择“证书”,单击“添加”。 选中“计算机帐户”单选按钮。单击Next。

在下一个屏幕中选择客户端计算机。单击Finish。 单击Close。 单击OK。 现在将证书安装到受信任的根证书颁发机构证书存储区中。这将允许所有用户信任该证书。

您确定您使用的SMTP服务器地址正确吗?

smtp.google.com和smtp.gmail.com都可以工作,但是SSL证书颁发给了第二个。