Many types of files are commonly used to deliver malware and other bogus content. In order to keep you as safe as possible we automatically block the following executable file extensions:
What about ZIP files?
Zip files are all too commonly used to sneak bogus executable files through various filters and scanners. In some cases they are password protected so the scanners are unable to see their contents.
It is because of this we have decided to quarantine all ZIP files. You'll find them listed in your Malware section of your Spam filter. Because these end up in the Malware section you are unable to release those messages without our assistance. This is simply how the filter tool works.
To view your quarantined Spam and Malware please see this article:
Send us a note to firstname.lastname@example.org asking for the release. Please let us know the name of the message as well as the date and time and we'll be happy to verify it's legitimacy and release the message to you. You can also call us at 925-249-1226 x1.