Post by CatBird
People are always sending me mail from MS Outlook
with picture files ending in the .eml extension.
The ".eml" extension is normally reserved
for Outlook Express email messages, rather than for pure image files.
That same extension is normally associated in Windows with Outlook Express
by default, and such isolated messages are then automatically opened
by (built-in) Outlook Express whenever Windows is asked to open them.
If a pure image file is mis-named with an .eml extension, then an image
viewing program can view it (e.g. built-in Windows Picture and Fax Viewer,
external IrfanView, XnView, etc., which now also have extra plugins for other
file types; Windows' "Open With" function can be used to select a program).
Additional information on .eml extension: