IMAP component for .NET

Mail.dll email component includes an excellent IMAP email component. Unleash the full potential of email management with Mail.dll’s outstanding IMAP email component.

It offers .NET developers an unparalleled tool for handling IMAP email protocol. From retrieving messages to managing folders and attachments, the IMAP component in Mail.dll simplifies complex tasks into user-friendly functions.

Mail.dll is available for all regular .NET framework versions as well as for most recent .net 6 and .net 7.

IMAP, short for Internet Message Access Protocol, is one of the two most prevalent Internet standard protocols for e-mail retrieval, the other being Post Office Protocol – POP3 (also available in Mail.dll).

IMAP has many advantages over POP3, most important are using folders to group emails, saving seen/unseen state of the messages and search capability.

This article is going to show how easy is to connect to use IMAP client from .NET, download and parse unseen messages.


The easiest way to install Mail.dll is to download it from nuget via Package Manager:

PM> Install-Package Mail.dll

Alternatively you can download Mail.dll directly from our website.

Connect to IMAP

First you need connect to IMAP server. You should use Imap class for that. Using block ensures that IMAP connection is properly closed and disposed when you’re done.

using(Imap imap = new Imap())

In most cases you should be using TLS secured connection – ConnectSSL method will choose a correct port and perform SSL/TLS negotiation, then you perform IMAP authentictation:

	imap.UseBestLogin("user", "password");

Mail.dll supports OAuth 2.0 for authentication, you can find OAuth2 samples for Office365 and Gmail on the Mail.dll samples page.

For Gmail you may want to use Gmail’s App Passwords.

Search for unseen emails

As IMAP groups messages into folder you need to select a well know INBOX folder. All new, received emails are first placed in the INBOX folder first:


Then you perform a search that find all unseen messages

List<long> uids = imap.Search(Flag.Unseen);

Download and parse emails

Finally you download emails one-by-one and parse them. You should use MailBuider class to parse emails:

var eml = imap.GetMessageByUID(uid);
IMail email = new MailBuilder().CreateFromEml(eml);

Entire code to download emails in .net

Entire code to download emails using IMAP is less than 20 lines:

using(Imap imap = new Imap())
	imap.ConnectSSL("");	// or Connect for no TLS
	imap.UseBestLogin("user", "password");

	List<long> uids = imap.Search(Flag.Unseen);

	foreach (long uid in uids)
		var eml = imap.GetMessageByUID(uid);
		IMail email = new MailBuilder().CreateFromEml(eml);

		string subject = mail.Subject;

and for those who like VB.NET more:

Using imap As New Imap()
	imap.UseBestLogin("user", "password")

	Dim uids As List(Of Long) = imap.Search(Flag.Unseen)

	For Each uid As Long In uids
		Dim mail As IMail = New MailBuilder()_

End Using

It can’t get much simpler than that!


You can use Mail.dll .NET IMAP component to:

It works perfectly with Exchange, Office365, Gmail and all other IMAP servers.

Just give Mail.dll a try and download it at: Mail.dll .NET IMAP component

Get Mail.dll



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