Today, digital communication in the business environment can hardly do without sending and receiving emails. These are loosely structured and often complex formats. So-called EML files are therefore used to facilitate the further use and standardized exchange of these important information carriers. These contain the entire content of the message as well as relevant key data in an organized text format. This enables uncomplicated documentation, but also harbors risks if users open an unknown EML file.
What is an EML file?
EML stands for "Electronic Mail" and refers to the existence of an e-mail as a file. It is this format that makes digital messages suitable for standardized processing. In addition to the specific content, it also contains information such as the sender, recipient, subject, attachments, time and various metadata. All of this is presented in a simply structured text format that is easy to read for both humans and machines and is therefore supported by numerous email applications. EML files are normally generated automatically when you download an email from your client in order to save it.

The specific benefits of the format may vary and relate to various tasks:
- Filing and documentation - Normally, emails can initially only be opened within an email program or browser. However, the messages often contain valuable information that may be relevant again later. As an EML file, they can be easily saved to any location and accessed again later. This also ensures compliance with various regulations in terms of audit-proof archiving supported.
- Data exchange and analysis - Emails are often used to transfer various files to another digital location or another person. The message is usually separated into header and body. In an EML file, everything can be summarized and moved in a uniform way or used as a backup. The file also enables smooth E-mail automationwhere data is read out automatically.
Open EML file in mail programs
The direct way to open an EML file is via Explorer and your personal mail program. The files are supported by the most common clients such as Windows Mail, Outlook or Thunderbird. Navigation takes you quickly to the app of your choice.

This step usually leads to the usual email display within the client. Which client is actually used for the process plays a subordinate role. The EML file is therefore also suitable for transferring emails when switching to another app.

However, one of the great advantages of EML is that the stored messages lose their dependency on mail clients.
Open EML file as plain text
It is easily possible to display the files as plain text. This does not require a complex conversion, it is sufficient to deal briefly with the EML file extension. This can be replaced by a simple renaming to TXT. It can then be opened using a text editor. With newer versions of Windows, this intermediate step may not be necessary and the "Edit in editor" option is available directly.

In any case, saving and viewing the file as plain text is accompanied by the display of countless special characters. The attachments also turn into code. This has little to do with the clarity of Outlook and the like. However, it does offer the advantage that the text content can be edited. Overall, EML is therefore a file that is easy to handle and virtually universally compatible. However, this is not without consequences.
An underestimated security risk
EML files currently enjoy too much trust from people and mail programs compared to the typical malware suspects such as .exe and co. This may be due to the text-based content or the fact that many security solutions only check the actual clean email, but not the attached EML files. The threat posed by dubious links or phishing instructions is enormous: by 2025, around 3.5 billion phishing emails sent, equivalent to 1.2%. The dubious content is often found in the main part, the body of the file, and is intended to encourage people to dial telephone numbers or support other scams.
As many users do not expect this when opening EMLs, it is not uncommon for damage to occur. The first step is therefore to create awareness of this. There are also various viewers that promise to open EML files under certain security aspects even without Outlook and other mail programs. In a corporate context, the approach to handling emails and various file formats such as EML is much more complex and the potential for damage is higher than in private use. However, in order to ensure smooth, secure and efficient processes, the support of a professional software partner is recommended.
Are you concerned about the secure handling of e-mails in your company? Send us directly a Message. We are happy to support you with secure e-mail management and data protection!
