File that may be sent by an automated emailing script or program; uses the generic filename filename.ext (the file's name and "ext" for "extension"); may be a file created in one of many text or binary formats.

If you receive an EXT file as an email attachment, it is generally not clear what the file format is. Therefore, it is best to contact the sender of the email to determine the file format. Many automated emailer code examples available on the Web use the generic string "filename.ext" when referring to the email attachment. Therefore, it's possible the script author did not replace the filename string with the appropriate attachment filename when sending the email.