The .eml format is used to be able to download emails locally and to be able to see more information about these emails.
If you have an email configured in a mail manager, when you download it from the mail manager, it is very likely that by default it will already be downloaded in .eml format.
In this guide we will show you how to download a file from the cdmon correoweb application (RoundCube).
To do this, you need to access the email account where the email to download is located from mail.domainname.com (in this example, we will use the domain bendiciones247.com).
Once you access the Roundcube webmail, you can see a screen with the different elements that will allow you to manage your messages.
Just select the email you want to download, and then go to the top right corner, to the "More" emoticon.
Then several actions will appear; you must go to "Download" and select Source (.eml).
You will now have the email downloaded locally on your device: