Convert msg file to eml

Aspose.Email Product Family
1

Dear Aspose Support Team,

We hope you are doing well.

We are currently facing issues when converting emails from .msg format to .eml format using the Aspose.Email library for .NET. We have tried two different approaches, but both exhibit errors:

First Approach: Using MailMessage.Load with MsgLoadOptions

In this method, we set PreserveTnefAttachments = true and PreserveEmbeddedMessageFormat = true. However, this results in five possible outcomes:

  1. A correctly generated .eml file.
  2. An .eml file that cannot be opened, displaying the error:
    3.“An error occurred in the underlying security system. An internal error occurred.”*
  3. An .eml file where the mail body is missing.
  4. A failure during loading, throwing an ArgumentOutOfRangeException.

Second Approach: Using MapiMessage.Load and Creating a New EML File

Here, we extract properties from the .msg file and use them to generate a new .eml file. However, this approach depends on how the properties are read. In some cases, the sender’s email address is read incorrectly (e.g., as /O=...), making it impossible to create a valid .eml file.

Request for Assistance

Could you please help us identify a more reliable approach for converting .msg to .eml?

Due to GDPR compliance and company policies, we are unable to share sample emails, but we will attach the code we currently use for your review.

Thank you for your support. We appreciate your assistance.

Best regards,
Nevena

2

@n.ceh

To convert .msg files to .eml format using the Aspose.Email library for .NET, you can utilize the MailMessage and MapiMessage classes effectively. Here’s a reliable approach to perform this conversion:

Step-by-Step Conversion Process

  1. Load the MSG File: Use the MailMessage.Load method with appropriate load options. If you want to preserve TNEF attachments, you can set the PreserveTnefAttachments option to true.

  2. Save as EML: After loading the MSG file, save it as an EML file using the MailMessage.Save method.

Example Code

Here’s a sample code snippet demonstrating how to convert a .msg file to .eml format:

using Aspose.Email;
using Aspose.Email.Mail;
using Aspose.Email.LoadOptions;

public class MsgToEmlConverter
{
    public static void ConvertMsgToEml(string msgFilePath, string emlFilePath)
    {
        // Load the MSG file
        MailMessage mailMessage = MailMessage.Load(msgFilePath, new MsgLoadOptions
        {
            PreserveTnefAttachments = true // Set to true if you want to preserve TNEF attachments
        });

        // Save the MailMessage as EML
        mailMessage.Save(emlFilePath, SaveOptions.DefaultEml);
    }
}

Handling Common Issues

  • Invalid EML Files: If you encounter issues where the generated EML file cannot be opened, ensure that the MSG file is not corrupted and that you are using the latest version of the Aspose.Email library.

  • Missing Mail Body: If the mail body is missing, check the original MSG file for any issues and ensure that the loading options are correctly set.

  • ArgumentOutOfRangeException: This may occur if the MSG file has unexpected data. Ensure that the MSG file is valid and conforms to expected formats.

Additional Considerations

  • If you are extracting properties from the MapiMessage class, ensure that you correctly handle the sender’s email address to avoid issues with formats like /O=.... You may need to parse the address correctly before saving it to the EML file.

By following this approach, you should be able to convert .msg files to .eml format reliably. If you continue to face issues, consider checking the documentation for more advanced options or troubleshooting tips.

Sources:
[1]: Convert MSG Files to Various Formats in C#|Documentation