随机“索引超出数组范围”作为 SmtpException

Question

我使用如下所示的 Send 方法随机遇到异常。我得到的例外是：

Exception information:
    Exception type: System.Net.Mail.SmtpException
    Exception message: Failure sending mail.

Inner exception information (level 1):
    Exception type: System.IndexOutOfRangeException
    Exception message: Index was outside the bounds of the array.

我的方法如下所示：

public void Send(string from, List<string> to, string subject, string body, List<string> attachments)
{
    var email = new MailMessage();
    var server = new SmtpClient();

    // Add each mail property
    email.From = new MailAddress(from);
    foreach (var t in to)
        email.To.Add(t);
    email.Subject = subject;
    email.IsBodyHtml = true;
    email.Body = body;
    foreach (var a in attachments)
        email.Attachments.Add(new Attachment(a));
    server.Send(email);
}

在调用此覆盖之前，我正在验证收件人列表和附件列表都至少有一个值并且该值有效。

异常发生在sever.Send上。

Answer 1

这听起来与this question about .NET 4.0 failing when sending emails with large attachments 相同。微软已经发布了bug fix here。