What is an "application/octet-stream" MIME attachment, and how can I see it?
A MIME attachment with the content type
"application/octet-stream" is a binary file. Typically, it
will be an application or a document that must be opened in an
application, such as a spreadsheet or word processor. If the
attachment has a filename extension associated with it, you may be
able to tell what kind of file it is. A .exe extension,
for example, indicates it is a Windows or DOS program
(executable), while a file ending in .doc is probably
meant to be opened in Microsoft Word.
No matter what kind of file it is, an application/octet-stream
attachment is rarely viewable in an email, Usenet, or web
client. If you are using a text-based client, such as
Pine, trn, or Lynx, save the
attachment to your account, and then transfer it to your personal
computer using SFTP. IU Webmail allows you to
save attachments directly to your personal computer; see In IU Webmail, how do I use attachments? If you are using a workstation-based client, such as
Thunderbird or Outlook, the application should
be able to extract and download the attachment automatically. After
downloading an attachment through any of these methods, you must then
open the attachment in the appropriate application to view its
contents.
Note: Before opening attachments, even from trusted
senders, you should follow the guidelines listed in Best practices for computer security.
In addition to the generic application/octet-stream content type, you may also encounter attachments that have different subtypes (e.g., application/postscript, application/x-macbinary, and application-msword). They are similar to application/octet-stream, but apply to specific kinds of files.
Last modified on May 13, 2009.
