× Help save net neutrality! Learn more.
OpenPop.NET Icon


Robust open source POP3 client and MIME parser written in C#

4.7 Stars (52)
112 Downloads (This Week)
Last Update:
Download OpenPop.NET 2.0.5.zip
Browse All Files


.NET library written in C# with a full implementation of a POP3 client. Easy to use but yet powerful. Includes a robust MIME parser backed by several hundred test cases.

The easiest way to install OpenPop.NET is via NuGet.
In Visual Studio's Package Manager Console, simply enter the following command:
Install-Package OpenPop.NET

Our homepage (http://hpop.sourceforge.net/) includes examples, documentation and a general introduction for email.

For more information, visit our project homepage.

Code is hosted on GitHub (https://github.com/foens/hpop).

OpenPop.NET Web Site




Public Domain


  • POP3
  • Robust MIME decoding
  • SSL and plain TCP supported


Other Useful Business Software

Identify and respond to threats before damage is done Icon

A SIEM that makes it easy to use logs for security, compliance, and troubleshooting.

Identify and respond to threats before damage is done Icon
SolarWinds® Log & Event Manager (LEM) delivers comprehensive Security Information and Event Management (SIEM) capabilities in a highly affordable, easy-to-use, and quick-to-deploy virtual appliance. LEM provides the visibility, security, and control that IT professionals need to alert on and respond to security threats, and assist in meeting the regulatory compliance guidelines of HIPAA, PCI DSS, SOX, and more. Try it free for 30 days!

User Ratings

ease 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 4 / 5
features 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 4 / 5
design 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 4 / 5
support 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5 3 / 5
Write a Review

User Reviews

  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    Stunningly simple, just works perfectly to parse out raw emails dropt into an s3 bucket. Totally demystifies MIME email messages.

    Posted 02/09/2017
  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    Failing to load email: System.FormatException: The specified media type is invalid. at System.Net.Mime.ContentType.set_MediaType(String value) at OpenPop.Mime.Header.HeaderFieldParser.ParseContentType(String headerValue) at OpenPop.Mime.Header.MessageHeader.ParseHeader(String headerName, String headerValue) at OpenPop.Mime.Header.MessageHeader.ParseHeaders(NameValueCollection headers) at OpenPop.Mime.Header.MessageHeader..ctor(NameValueCollection headers) at OpenPop.Mime.Header.HeaderExtractor.ExtractHeadersAndBody(Byte[] fullRawMessage, MessageHeader& headers, Byte[]& body) at OpenPop.Mime.MessagePart.ParseMultiPartBody(Byte[] rawBody) at OpenPop.Mime.MessagePart.ParseBody(Byte[] rawBody) at OpenPop.Mime.MessagePart..ctor(Byte[] rawBody, MessageHeader headers) at OpenPop.Mime.Message..ctor(Byte[] rawMessageContent, Boolean parseBody) at OpenPop.Pop3.Pop3Client.GetMessage(Int32 messageNumber)

    Posted 11/03/2014
  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    I have a error, how I solve this? ERROR:The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or a non-white space character among the padding characters. what's meaning?

    Posted 08/01/2014
  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    Not able to connect to mail server.Most of the times it gives error like :No connection could be made because the target machine actively refused it OR An invalid argument was supplied Please help!!!

    Posted 05/19/2014
  • 1 of 5 2 of 5 3 of 5 4 of 5 5 of 5

    Used this library in online business, so thanks for your effort in creating this library and supporting website. Well worth a donation to the developers. :)

    Posted 04/17/2014
Read more reviews

Additional Project Details

Intended Audience

Advanced End Users, Developers

Programming Language




Thanks for helping keep SourceForge clean.

Screenshot instructions:
Red Hat Linux   Ubuntu

Click URL instructions:
Right-click on ad, choose "Copy Link", then paste here →
(This may not be possible with some types of ads)

More information about our ad policies

Briefly describe the problem (required):

Upload screenshot of ad (required):
Select a file, or drag & drop file here.

Please provide the ad click URL, if possible:

Get latest updates about Open Source Projects, Conferences and News.

No, Thank you