Opening eml-files with Outlook

By default, after installing Outlook 2010 or later, eml-files will automatically open with Outlook. If they don’t, you can make them open with Outlook again by changing the default application for eml-files.

If you are still running Outlook 2003 or Outlook 2007, you’ll need to make a change in the Registry to be able to open eml-files with Outlook.

Changing the default application for eml-files to Outlook

Making Outlook the default application for eml-files is quite easy even though the location to do this in Windows might be unfamiliar territory to you.

1. Open the Default Apps dialog
   • Windows 7
     Start-> Default Programs-> Associate a file type or protocol with a program
   • Windows 8 and Windows 10 (Control Panel)
     Start-> type: “Default Programs”-> Associate a file type or protocol with a program
   • Windows 10 (Settings)
     Start-> Settings-> Apps-> Default apps-> Choose default apps by file type (text link at the bottom)
2. From the long list of file extensions, look for .eml.
3. Click on the application icon behind it (in the Settings app of Windows 10 and Windows 8) or click on the “Change program…” button at the top (Control Panel).
4. From the pop-up window, select Outlook.

Setting the default application for eml-files to Outlook in Windows 10.

Outlook 2003 and Outlook 2007: Registry files

Before implementing the changes below, make sure you have the latest updates installed for your version of Outlook. This is because support for opening eml-files in Outlook 2003 and Outlook 2007 was only introduced after their releases.

Once Outlook is fully up-to-date, download this zip file.

The zip file contains 5 files;

• readme.txt
  Contains additional info before getting started
• eml-Outlook2003-Win32.reg
  For Outlook 2003 on a 32-bit Windows version
• eml-Outlook2003-Win64.reg
  For Outlook 2003 on a 64-bit Windows version
• eml-Outlook2007-Win32.reg
  For Outlook 2007 on a 32-bit Windows version
• eml-Outlook2007-Win64.reg
  For Outlook 2007 on a 64-bit Windows version

Execute the reg-file that matches your version of Outlook and Windows by double clicking on it. You’ll get a confirmation when it has been successfully added to the registry.

Note 1: To import this registry file, you’ll need to have Administrator rights on the computer.

Note 2: You can easily save the opened eml-message to a folder within Outlook by using the “Move To Folder” command (CTRL+SHIFT+V).

Outlook 2003 and Outlook 2007: Custom installation paths

The registry keys are based on the default installation path of Outlook. If you for some reason installed it to a different location, then you can modify the path accordingly for the following keys in the reg-file with Notepad or after importing it via Regedit;

HKEY_CLASSES_ROOT\Outlook.File.eml\DefaultIcon 
HKEY_CLASSES_ROOT\Outlook.File.eml\shell\Open\command 
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Outlook.File.eml\DefaultIcon 
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Outlook.File.eml\shell\Open\command