At IU, what types of attachments are blocked from my email account?

To protect computers at Indiana University, UITS has enabled filters for attachments that have been known to carry viruses.

If you know your file is safe and need to share it, you can rename the file, using either a different extension or no extension, and then attach it to your email message. See At IU, how can I send email with a blocked attachment type? Alternatively, you can share the file using one of IU's file-sharing services, such as Box or Slashtmp; see At IU, how can I collaborate on documents and share data with others?

The UITS attachment filters block the following file types:


Note: Archive files (e.g., zip or tar files) that contain any of the above file types will also be blocked.

IU Exchange accounts

The IU Exchange email system uses software called Microsoft Forefront to filter mail for possible viruses. Microsoft Forefront strips blocked files from messages leaving the IU Exchange system and delivers the messages to recipients, without the attachments. If someone from outside the IU Exchange environment sends a message containing one of the blocked attachment types to your Exchange account, you will not receive the attachment or the message. The filtering software at the external mail relays blocks the entire message, and will generate a nondeliverable response (NDR) message to the sender. However, it's up to the sender's email system to accept NDRs. Because of the amount of NDR traffic that spam and viruses cause, many systems do not accept NDRs.

If you send a message from an Exchange account with an .shb, .shs, or .vbs attachment, you'll get an automated message from Microsoft Forefront with a subject line similar to "Forefront found FILE FILTER= *.ext file", where "ext" is the attached file's extension.

If you send a .com, .exe, .pif, or .scr attachment from an Exchange account, Microsoft Forefront will replace the attachment with the text message "Microsoft Forefront Security for Exchange Server removed filename.ext since it was found to match the FILE FILTER= *.ext file filter." (where "filename" is the name of the attachment, and ".ext" is the specific extension of the attached file). Exchange will then deliver the original message without the attachment.

This is document ajch in the Knowledge Base.
Last modified on 2015-03-05.

  • Fill out this form to submit your issue to the UITS Support Center.
  • Please note that you must be affiliated with Indiana University to receive support.
  • All fields are required.

Please provide your IU email address. If you currently have a problem receiving email at your IU account, enter an alternate email address.

  • Fill out this form to submit your comment to the IU Knowledge Base.
  • If you are affiliated with Indiana University and need help with a computing problem, please use the I need help with a computing problem section above, or contact your campus Support Center.

Please provide your IU email address. If you currently have a problem receiving email at your IU account, enter an alternate email address.