我是C＃的新手并且开始学习 我尝试发送一封谷歌邮件，但却抛出了这个错误 请帮我完成我的工作
（SMTP服务器需要安全连接或客户端未经过身份验证。服务器响应为：5.5.1需要身份验证。了解详情）
using (MailMessage mm = new MailMessage("sender@gmail.com", txtEmail.Text))
{
mm.Subject = "Account Activation";
string body = "Hello " + txtUsername.Text.Trim() + ",";
body += "<br /><br />Please click the following link to activate your account";
body += "<br /><a href = '" + Request.Url.AbsoluteUri.Replace("CS.aspx", "CS_Activation.aspx?ActivationCode=" + activationCode) + "'>Click here to activate your account.</a>";
body += "<br /><br />Thanks";
mm.Body = body;
mm.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient();
smtp.Host = "smtp.gmail.com";
smtp.EnableSsl = true;
NetworkCredential NetworkCred = new NetworkCredential("sender@gmail.com", "<password>");
smtp.UseDefaultCredentials = true;
smtp.Credentials = NetworkCred;
smtp.Port = 587;
smtp.Send(mm);
}
答案 0 :(得分：0)
使用gmail将EnableSSL设置为true并将Port设置为587是正确的，因为SmtpClient类不适用于端口465.请参阅本文http://www.codeproject.com/KB/IP/GmailSmtp.aspx?q=SmtpClient+ssl+yahoo 我认为问题是smtp.UseDefaultCredentials = true。 尝试删除此行。
您好。
答案 1 :(得分：0)
你应该收到来自谷歌的电子邮件，说明他们已经阻止访问安全性较低的应用。
您需要设置UseDefaultCredentials = false，并且需要允许访问来自https://www.google.com/settings/security/lesssecureapps?rfn=27&rfnc=1&asae=2&anexp=lbe3-R2_C的安全性较低的应用
我已经这样做了，我的应用程序可以使用Gmail发送电子邮件。
答案 2 :(得分：0)
To Send email using Gmail server we need to set following thing.Use these namespaces in C#.
1. using System.IO;
2. using System.Net;
3. using System.Net.Mail;
MailMessage Class Properties
Following are the required properties of the MailMessage class.
- From – Sender’s email address
- To – Recipient(s) Email Address
- CC –Carbon Copies (if any)
- BCC – Blind Carbon Copies (if any)
- subject –Subject of the Email
- Body – Body of the Email
- IsBodyHtml – Specify whether body contains text or HTML tag.
- Attachments – Attachments(if any)
- ReplyTo – ReplyTo Email address.
SMTP Class Properties
Following are the properties of the SMTP class.
- Host – SMTP Server URL (Gmail: smtp.gmail.com)
- EnableSsl – Specify whether your host accepts SSL Connections (Gmail: True)
- UseDefaultCredentials – Set to True in order to allow authentication based on the Credentials of the Account used to send emails
- Credentials – Input valid username and password
- Port – Assign port number for (Gmail: 587)
Finally here is your Code.
using (MailMessage mm = new MailMessage(from, to))
{
mm.Subject = "Account Activation";
string body = "Hello " + your username.Trim() + ",";
body += "<br /><br />Please click the following link to activate your account";
body += "<br /><a href = '" + new Uri("http://www.google.com", true).AbsoluteUri + "<a>Click here to activate your account.</a>";
body += "<br /><br />Thanks";
mm.Body = body;
mm.IsBodyHtml = true;
SmtpClient smtp = new SmtpClient();
smtp.Host = "smtp.gmail.com";
smtp.EnableSsl = true;
NetworkCredential NetworkCred = new NetworkCredential(username, password);
smtp.UseDefaultCredentials = true;
smtp.Credentials = NetworkCred;
smtp.Port = 587;
smtp.Send(mm);
}
如果您收到错误，请执行以下操作： -
- SMTP服务器需要安全连接或客户端未经过身份验证。服务器响应为：5.5.1需要身份验证。
然后执行以下步骤： - 点击下面的链接。 - https://www.google.com/settings/security/lesssecureapps
单击单选按钮启用。
它会起作用。
代码已经过测试。感谢..
答案 3 :(得分：0)
您正在为您的Gmail帐户定义登录凭据：
I combine both styles you have provided:
<Charting:Chart
x:Name="LineChart" Grid.Column="1" FontSize="16" VerticalAlignment="Top"
HorizontalAlignment="Left" Margin="94,27,0,0"
FontWeight="SemiBold" Width="651" Height="506">
<Charting:LineSeries
Title="Station1" Margin="0" FontSize="16" Foreground="Blue" FontWeight="SemiBold" IndependentValuePath="Q_interval" DependentValuePath="Q_size" IsSelectionEnabled="True">
<Charting:LineSeries.Style>
(1)
<Style TargetType="Charting:LineSeries">
<Setter Property="IsTabStop" Value="False" />
<Setter Property="PolylineStyle">
<Setter.Value>
<Style TargetType="Polyline">
<Setter Property="StrokeThickness" Value="3" />
<Setter Property="StrokeMiterLimit" Value="1" />
</Style>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Charting:LineSeries">
<Canvas x:Name="PlotArea">
<Polyline
Style="{TemplateBinding PolylineStyle}"
Stroke="Blue"
Points="{TemplateBinding Points}" />
</Canvas>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Charting:LineSeries.Style>
(2)
<Charting:LineSeries.DataPointStyle>
<Style TargetType="Charting:LineDataPoint">
<Setter Property="Width" Value="20" />
<Setter Property="Height" Value="20" />
<Setter Property="Background" Value="Blue"/>
<Setter Property="FontWeight" Value="SemiBold"/>
</Style>
</Charting:LineSeries.DataPointStyle>
</Charting:LineSeries>
</Charting:Chart>
但是，您通过将NetworkCredential NetworkCred = new NetworkCredential("sender@gmail.com", "<password>");
属性设置为true来覆盖这些详细信息。
UseDefaultCredentials您需要删除该行代码，因为它告诉您的应用程序尝试使用您的Windows凭据登录gmail。或者，如果这不起作用，您可以在提供新的NetworkCredentials之前将其设置为false：
smtp.UseDefaultCredentials = true;
之后，如果您不断收到错误消息，则需要进入gmail帐户安全设置并允许安全性较低的应用程序。
答案 4 :(得分：0)
您好我的朋友我只是想出了这个错误，它只是您没有更改sender@gmail.com和密码的任何内容，只需输入您创建的Gmail和密码，就像您一样在下面的修改中看到，代码实际上没有任何问题，只是把你创建的电子邮件放到那个gmail的密码上，实际上上面的所有答案都是正确的但是你必须删除那个＆＃34;＆lt;＆gt; ＆＃34;到你的密码，你没有将sender@gmail.com改为各自的gmail ......
NetworkCredential NetworkCred = new NetworkCredential("sender@gmail.com", "<password>");
NetworkCredential NetworkCred = new NetworkCredential("yourgmail.com", "yourpassword");