If you wish to open and view the hexadecimal files, you must use some program or application for this. There is no other way of doing this. You can try any Hex Editor (https://www.4n6soft.com/free-hex-editor/) available. One such utility is the free Hex Editor tool. With this, you can view as well as edit your Hex file directly. 

The Hex editor also gives many different options to edit the files. It can be installed on any Windows computer.

If you are looking for a solution for queries like, how to convert eml to pdf, batch convert eml to pdf, eml to pdf converter software, convert eml to pdf adobe, free conversion of eml file to pdf, eml to pdf converter free download, convert eml to pdf with attachments, how to extract pdf from eml and so on.
In order to solve above queries, I would like to suggest you to try Advik EML to PDF Converter. The tool has the simplest user interface, which makes it easier for users to convert EML to PDF. Even after email conversion process, the attachments remain intact with the pdf file.

How to Batch Convert EML to PDF?

1. Launch Advik EML to PDF Converter.
2. Browse and add EML files.
3. Select Desired Output path.
4. Click on Convert button.

This is how you can convert multiple EML files to PDF Adobe.