What is the name and location of the file where eM Client stores received e-mails?

I need to know where they are if I want back them up.

Hi, you can export your emails to a folder if you want to back them up, however all your mail data is stored in multiple database files in eM Client’s database folder.
You can backup the whole database folder if you go to your local folder > App Data (hidden folder) > Roaming > eM Client.

The mails are stored in multiple mail_*.dat, I do not recommend backing up just these files, it might not be a working solution when you actually need to import your backed up data.

Thank you for understanding,