Moving mail in local folders from Windows to Linux is actually fairly straightforward — with the help of a plug-in for Thunderbird. Microsoft Mail stores email locally in .eml files. There is a plug-in for Thunderbird, ImportExportTools, which does a really nice job of importing .eml files.
This procedure is for the Windows Mail application, not for Outlook. It should work for any email client which stores email in local folders in the .eml format.
Getting the Data Out of Windows
The first thing to do is to get the email data out of Windows. I found that there are no options within Windows Mail to actually export the email. Instead we will copy the entire directory structure that contains the .eml email files. On the Windows computer the procedure to get the email is:
- Locate the Local folders directory in the home directory of the user.
- Copy the directory to a location from which it can be accessed later on the Linux computer. A USB drive of some type is good for this. You can zip the entire directory to compress it or just copy it as-is.
Installing the Plug-in
- Download the xpi file using the link at the bottom of this page. Right click on the link and choose Save link as and then save the file to /tmp or someplace in your home directory structure where you can get at it.
- In Thunderbird, go in Tools ==> Addons and click on the Install button.
- Locate and select the xpi file you downloaded in step 1 and click on the Open button.
- In the Software installation window click on the item ImportExportTools.
- Click on the Install now button.
- Restart Thunderbird.
Importing the Email
On the Linux computer, the procedure to import the email is simple once the plug-in is installed.
- Copy the email from the USB drive that you stored it on to /tmp on the Linux computer. You could also simply access it from the USB drive. It just needs to be located somewhere that you can access it easily.
- Unzip the file if necessary.
- In Thunderbird select from the Menu bar, Tools Menu==>ImportExportTools. A new window is displayed.
- In the context menu on folders panel choose Import/Export==>Import of all the eml files existing in a directory==>Also from its subdirectories
- Use the file manager to locate and select the Local folders directory.
- Click on the Open button.
- The import should take place automatically. You should be able to see the folders and emails being imported as it occurs.
Refer to the information at the Kaosmos website in the References section below for details and limitations of this Thunderbird extension.