Message blocking

For security reasons, organizations may have a policy for blocking delivery of email messages by certain general characteristics, such as:

• Attachment size is too large

• Attachment extension type is blocked, i.e., messages containing .ZIP extension or .exe extension attachments may be blocked.
  
  Note: Many viruses are spread through email messages containing .ZIP or .EXE files

• All attachments, regardless of type (might be temporarily used during virus or spam attacks)

The exact blocking policy in place at your site is determined by your administrator. If you think you should be getting messages that haven't been received, check with your administrator.

Senders whose messages were blocked may not receive notification that their messages were not delivered.