Aspose.Email  for .NET

eSign MBOX Formats in C#

Native and high performance MBOX message electronic signature using server-side Aspose.Email for .NET APIs, without the use of any software like Microsoft or Open Office, Adobe PDF.

How to Digitally Sign MBOX File Using C#

In order to electronically sign MBOX file, we’ll use

Aspose.Email for .NET

API which is a feature-rich, powerful and easy to use digital signature API for C# platform. Open


package manager, search for Aspose.Email and install. You may also use the following command from the Package Manager Console.


PM> Install-Package Aspose.Email

Steps for e-Signing MBOX Files in C#

A basic message digital signature with

Aspose.Email for .NET

APIs can be done with just few lines of code. One can sign email processing documents by adding text, image or draw professional digital signature to the email files as well as save result in MSG and EML formats.

  • Load all the MBOX files with full path.
  • Set the style of text like font, font size, color etc.
  • Set the Signature text.
  • Save MBOX file, You will get the document with signature inserted.

System Requirements

Our APIs are supported on all major platforms and Operating Systems. Before executing the code below, please make sure that you have the following prerequisites on your system.

  • Microsoft Windows or a compatible OS with .NET Framework, .NET Core, and Xamarin Platforms
  • Development environment like Microsoft Visual Studio
  • Aspose.Email for .NET DLL referenced in your project - Install from NuGet using the Download button above

e-Sign MBOX Files - C#

var mail = MapiHelper.GetMapiMessageFromFile(inputFilePath);

var htmlDocument = new Aspose.Html.HTMLDocument(mail.BodyHtml, "");

var element = htmlDocument.CreateElement("Signature");
element.InnerHTML = "Signature Text (Style it with css)";

var folderPath = "directorypath";
var filePath = folderPath + "Merged.html";
var content = System.IO.File.ReadAllText(filePath);
mail.SetBodyContent(content, BodyContentType.Html);

mail.Save(Path.Combine(outputFolderPath, Path.GetFileNameWithoutExtension(inputFilePath) + " Signed.mbox"), new EmlSaveOptions(MailMessageSaveType.MboxFormat));  
  • About Aspose.Email for .NET API

    Aspose.Email is a Microsoft Outlook and Thunderbird formats parsing solution. One can easily create, manipulate, convert email and storage formats such as MSG, EMLX, EML and MHT. Handling of email attachments, customization of message headers and implementation of different network protocols like POP3, IMAP & SMTP to send & receive emails is much easier. Its a standalone API and does not require Microsoft Outlook or any other software installation.

    Online MBOX eSignature Live Demos

    MBOX What is MBOX File Format

    MBox file format is a generic term that represents a container for collection of electronic mail messages. The messages are stored inside the container along with their attachments. Messages from an entire folder are saved in a single database file and new messages are appended to the end of the file. Numerous applications and API provide support for MBox file format such as Apple Mail and Mozilla Thunderbird.

    Read More

    Other Supported Files for Electronic Signatures

    Using C#, One can also digitally sign many other formats including.

    EML (Outlook Email Messages)
    MSG (Outlook & Exchange Format)
    OST (Offline Storage Files)
    PST (Outlook Personal Storage Files)