Yes, it's definitely a .xlsx file. So the .bin file is needed to open the spreadsheet? The sender doesn't know that he's sending the .bin file...He's just sending the spreadsheet...
Main Topics
Browse All TopicsThere are a number of extensions our mail filters block for inbound emails;, .exe, .bat...One of those extensions by default (in the program we us: Symantec Mail Security for SMTP) is a .bin file.
On two occasions, someone has sent us a .xlsx and a .bin file has been removed from the email and the spradsheet will not open. I know I could just allow .bin files and it would work but what do you think is happening here? Why is there a .bin file in the email and what does that have to do with the .xlsx spreadsheet?
Thanks in advance!
This Question has been solved and asker verified All Experts Exchange premium technology solutions are available to subscription members.
Experts Exchange has been collecting answers to technology questions since 1996…3 million and counting! If you have a question, chances are we already have your answer.
If you can't find the exact answer you're looking for, ask our exclusive community of 50,000 experts. You’ll get a personalized answer from a trusted professional.
Thousands of free tech tips, tricks, how-to’s and tutorials are available in our peer reviewed articles section. See for yourself how smart our experts are, no login required.
Access the answers to your technology questions today.
30-day free trial. Register in 60 seconds.
Members of the expert community talk about why the experience at Experts Exchange is different than what you will find anywhere else.

Try it out and discover for yourself.
30-day free trial. Register in 60 seconds.
Join the community of experts here and help other tech pros by answering question in your area of expertise. You can earn FREE access to all Experts Exchange's premium features and resources.
Oh yes, I forgot about printer settings! Yes, they are always stored as bin files. There's quite a good list of things that can be included as bin files here:
http://www.codeprojec
Regards,
Ro
PS You could probably tell your mail security to ignore xlsx files?
The mail security is triggering on the .bin file not the .xlsx file. Also found this:
Email Virus Scanner Quarantines Office 2007 Documents
When a user receives a Office 2007 documents saved in the Office OpenXML format (e.g. .docx, .xlsx, pptx) as an email attachment, occasional files may be quarantined or otherwise flagged as infected by an email antivirus program. This is caused by the virus scanner flagging the file because it contains a binary file (.bin).
The Office OpenXML format files are actually zip files which contain multiple files within them. Antivirus software may recognize them as such, unzip them, and analyze the contents individually. Among the files which an Office OpenXML document can contain are files such as oleObject1.bin (containing embedded OLE objects) or PrinterSettings1.bin (containing printer settings). These .bin files may cause the attachment to trigger a policy in the virus scanner which blocks executables or filters common executable extensions (.exe, .bin, .com, .bat, .pif, etc.).
Potential workarounds include turning off quarantining of executable attachments, allowing attachments with the .bin extension, or not scanning zips, but both of these are potentially too dangerous to seriously consider. Until the Office OpenXML format becomes more prevalent and/or the antivirus vendors find an intelligent solution to this issue, it may be easier to individually release these files from quarantine.
I don't really want to not scan .bin attachments but there doesn't seem to be much of a workaround...
Thanks for your help!
Business Accounts
Answer for Membership
by: roryaPosted on 2009-09-02 at 09:02:41ID: 25242465
bin files are created for macros and OLE objects embedded in the files. If it's definitely an .xlsx and not an .xlsm, then the bin file presumable relates to an embedded object, not a VBA project.
Regards,
Rory