To enable POP3 in Gmail:
Remember that Gmail only allows secure SSL connections so we need to use ConnectSSL method.
You can use SupportedAuthenticationMethodsto retrieve all authentication methods supported by the server:
// C#
using (Imap client = new Imap())
{
client.ConnectSSL("imap.example.org");
client.UseBestLogin("user", "password");
Console.WriteLine("Supported methods:");
foreach (var method in client.SupportedAuthenticationMethods())
{
Console.WriteLine(method.Name);
}
Console.WriteLine("Supports CramMD5:");
bool supportsCramMD5 = client.SupportedAuthenticationMethods()
.Contains(ImapAuthenticationMethod.CramMD5);
Console.WriteLine(supportsCramMD5);
client.Close();
}
' VB.NET
Using client As New Imap()
client.ConnectSSL("imap.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported methods:")
For Each method As ImapAuthenticationMethod In client.SupportedAuthenticationMethods()
Console.WriteLine(method.Name)
Next
Console.WriteLine("Supports CramMD5:")
Dim supportsCramMD5 As Boolean = client.SupportedAuthenticationMethods() _
.Contains(ImapAuthenticationMethod.CramMD5)
Console.WriteLine(supportsCramMD5)
client.Close()
End Using
For example Gmail produces following output:
Supported method s: IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 UIDPLUS COMPRESS Supports CramMD5: False
We take great care for the API to look similar for all protocols (IMAP, POP3, SMTP).
Here’s the sample for POP3:
// C#
using (Pop3 client = new Pop3())
{
client.ConnectSSL("pop3.example.org");
client.UseBestLogin("user", "password");
Console.WriteLine("Supported methods:");
foreach (var method in client.SupportedAuthenticationMethods())
{
Console.WriteLine(method.Name);
}
Console.WriteLine("Supports CramMD5:");
bool supportsCramMD5 = client.SupportedAuthenticationMethods()
.Contains(Pop3AuthenticationMethod.CramMD5);
Console.WriteLine(supportsCramMD5);
client.Close();
}
' VB.NET
Using client As New Pop3()
client.ConnectSSL("pop3.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported methods:")
For Each method As Pop3AuthenticationMethod In client.SupportedAuthenticationMethods()
Console.WriteLine(method.Name)
Next
Console.WriteLine("Supports CramMD5:")
Dim supportsCramMD5 As Boolean = client.SupportedAuthenticationMethods() _
.Contains(Pop3AuthenticationMethod.CramMD5)
Console.WriteLine(supportsCramMD5)
client.Close()
End Using
Here’s the sample for SMTP:
// C#
using (Smtpclient = new Smtp())
{
client.Connect("smtp.example.org");
client.UseBestLogin("smtp", "password");
Console.WriteLine("Supported methods:");
foreach (var method in client.SupportedAuthenticationMethods())
{
Console.WriteLine(method.Name);
}
Console.WriteLine("Supports CramMD5:");
bool supportsCramMD5 = client.SupportedAuthenticationMethods()
.Contains(SmtpAuthenticationMethod.CramMD5);
Console.WriteLine(supportsCramMD5);
client.Close();
}
' VB.NET
Using client As New Smtp()
client.Connect("smtp.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported methods:")
For Each method As SmtpAuthenticationMethod In client.SupportedAuthenticationMethods()
Console.WriteLine(method.Name)
Next
Console.WriteLine("Supports CramMD5:")
Dim supportsCramMD5 As Boolean = client.SupportedAuthenticationMethods() _
.Contains(SmtpAuthenticationMethod.CramMD5)
Console.WriteLine(supportsCramMD5)
client.Close()
End Using
You can use SupportedExtensionsmethod to retrieve all protocol extensions supported by the server:
// C#
using (Imap client = new Imap())
{
client.ConnectSSL("imap.example.org");
client.UseBestLogin("user", "password");
Console.WriteLine("Supported extensions:");
foreach (ImapExtension extension in client.SupportedExtensions())
{
Console.WriteLine(extension.Name);
}
Console.WriteLine("Supports IDLE:");
bool supportsIdle = client.SupportedExtensions()
.Contains(ImapExtension.Idle);
Console.WriteLine(supportsIdle);
client.Close();
}
' VB.NET
Using client As New Imap()
client.ConnectSSL("imap.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported extensions:")
For Each extension As ImapExtension In client.SupportedExtensions()
Console.WriteLine(extension.Name)
Next
Console.WriteLine("Supports IDLE:")
Dim supportsIdle As Boolean = client.SupportedExtensions() _
.Contains(ImapExtension.Idle)
Console.WriteLine(supportsIdle)
client.Close()
End Using
For example Gmail produces following output:
Supported extensions: IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 UIDPLUS COMPRESS Supports IDLE: True
We take great care for the API to look similar for all protocols (IMAP, POP3, SMTP).
Here’s the sample for POP3:
// C#
using (Pop3 client = new Pop3())
{
client.ConnectSSL("pop3.example.org");
client.UseBestLogin("user", "password");
Console.WriteLine("Supported extensions:");
foreach (Pop3Extension extension in client.SupportedExtensions())
{
Console.WriteLine(extension.Name);
}
Console.WriteLine("Supports TOP:");
bool supportsTop= client.SupportedExtensions()
.Contains(Pop3Extension.Top);
Console.WriteLine(supportsTop);
client.Close();
}
' VB.NET
Using client As New Pop3()
client.ConnectSSL("pop3.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported extensions:")
For Each extension As Pop3Extension In client.SupportedExtensions()
Console.WriteLine(extension.Name)
Next
Console.WriteLine("Supports TOP:")
Dim supportsTop As Boolean = client.SupportedExtensions() _
.Contains(Pop3Extension.Top)
Console.WriteLine(supportsTop)
client.Close()
End Using
Here’s the sample for SMTP:
// C#
using (Smtpclient = new Smtp())
{
client.Connect("smtp.example.org");
client.UseBestLogin("smtp", "password");
Console.WriteLine("Supported extensions:");
foreach (SmtpExtension extension in client.SupportedExtensions())
{
Console.WriteLine(extension.Name);
}
Console.WriteLine("Supports STARTTLS:");
bool supportsStartTLS = client.SupportedExtensions()
.Contains(SmtpExtension.StartTLS);
Console.WriteLine(supportsStartTLS);
client.Close();
}
' VB.NET
Using client As New Smtp()
client.Connect("smtp.example.org")
client.UseBestLogin("user", "password")
Console.WriteLine("Supported extensions:")
For Each extension As SmtpExtension In client.SupportedExtensions()
Console.WriteLine(extension.Name)
Next
Console.WriteLine("Supports STARTTLS:")
Dim supportsStartTLS As Boolean = client.SupportedExtensions() _
.Contains(SmtpExtension.StartTLS)
Console.WriteLine(supportsStartTLS)
client.Close()
End Using
RFC 1939 specification says:
“The unique-id of a message is an arbitrary server-determined string, [...], which uniquely identifies a message within a maildrop and which persists across sessions.”
“The server should never reuse an unique-id in a given maildrop, for as long as the entity using the unique-id exists.”
So in theory if the email is deleted server may reuse the same unique-id.
“While it is generally preferable for server implementations to store arbitrarily assigned unique-ids in the maildrop, this specification is intended to permit unique-ids to be calculated as a hash of the message.
Clients should be able to handle a situation where two identical copies of a message in a maildrop have the same unique-id.”
Mail.dll will not throw exception in such case, but please note that as internally Mail.dll uses dictionaries to store unique-ids, Pop3.GetAll() method will not return duplicates.
Mail.dll is a rock solid product, however most email servers don’t follow rigorously the RFC specifications. In the following few steps we’ll help you gather the information we need to make Mail.dll clients better.
If you are having the problems parsing a single message please go here
1.
First please check if you have the latest version installed.
2.
Please identify the command/set of commands that cause problems.
3.
Enable logging for Mail.dll clients:
// C# version: Log.Enabled = true;
// VB.NET version: Log.Enabled = True
You can observe standard Visual Studio trace output or add a custom listener to Trace.Listeners collection.
You can also enable logging using App.config file:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.diagnostics>
<switches>
<add name="Mail.dll" value="True" />
</switches>
</system.diagnostics>
</configuration>
You can create your custom TraceListener that writes log to file:
// C# version:
internal class MyListener : TextWriterTraceListener
{
public MyListener(string fileName)
: base(fileName)
{
}
public override void Write(string message, string category)
{
if (category == "Mail.dll")
base.Write(message, category);
}
public override void WriteLine(string message, string category)
{
if (category == "Mail.dll")
base.WriteLine(message, category);
}
}
' VB.NET version Friend Class MyListener Inherits TextWriterTraceListener Public Sub New(fileName As String) MyBase.New(fileName) End Sub Public Overrides Sub Write(message As String, category As String) If category = "Mail.dll" Then MyBase.Write(message, category) End If End Sub Public Overrides Sub WriteLine(message As String, category As String) If category = "Mail.dll" Then MyBase.WriteLine(message, category) End If End Sub End Class
…then add it to Listeners collection:
// C# version: Log.Enabled = true; Trace.Listeners.Add(new MyListener(@"c:mail_log.txt")); Trace.AutoFlush = true;
// VB.NET version:
Log.Enabled = True
Trace.Listeners.Add(New MyListener("c:mail_log.txt"))
Trace.AutoFlush = True
4.
Perform the operations that cause the problems, and save the log to file.
You can remove username and password, but please do not modify the file extensively. If you do, it may be impossible to reproduce the issue.
In particular do not change new line format nor encoding.
5.
Please answer following questions:
6.
Finally please zip the log file and send it as attachment, along with all the answers to 
.
Thanks!
