Mailprotector blocks high-risk extensions from being relayed inbound or outbound through our security layers. If you/your users attempt to send a banned extension, they will receive the following response (bounce/NDR) with the following explanation and corrective actions.
A file you sent was blocked by CloudFilter™
You are trying to send an email message with a file attachment to a recipient protected by CloudFilter email security from Mailprotector®. The file attachment that you are trying to send contains a three-letter extension which makes this file "executable."
Computer viruses are often spread as programs attached to email messages. These messages usually trick the recipient into clicking on the file and "executing" the program. However, some are able to automatically execute themselves when an email message is merely previewed by the recipient. Because of this, the following file extensions are automatically blocked by CloudFilter:
Blocked Extensions
| .ade | Access Project Extension |
| .mdb | Access Database |
| .adp | Access Project file |
| .mde | Access file |
| .bas | BASIC Program |
| .msc | Common Console Doc (Win2k) |
| .bat | DOS Batch File Script |
| .msi | Installer Program |
| .chm | Compiled HTML file |
| .msp | Windows Installer Patch file |
| .cmd | 1st Reader External Command Menu |
| .mst | Windows Installer Transform file |
| .com | Command file (Program) |
| .pcd | P-Code Compiled Test Script |
| .cpl | Control Panel Module |
| .pif | Program Info file (Win 3.1) |
| .crt | Certificate file |
| .reg | Registration file |
| .exe | Executable file (Program) |
| .scr | Screensaver |
| .hlp | Windows Help file |
| .sct | FoxPro Form |
| .hta | HTML file |
| .shs | Shell Scrap file |
| .inf | Package Information file |
| .url | Internet Shortcut file |
| .ins | Install Script |
| .vbs | VisualBasic Program |
| .isp | Sign-up file (X-Internet) |
| .vbe | VisualBasic Related |
| .jsp | JavaScript |
| .wsf | Windows Script Component |
| .lnk | Shortcut file (Windows) |
| .wsh | Windows Script file |
| .wsc | Windows Script Host Settings file |
| .js | JavaScript |
Question: How can I send my message?
Answer: The first option is to rename your file attachment. For example, you could rename your attachment to "filename.txt" with instructions in the body of your message as to what the appropriate extension should be. Another option is to compress your file(s) with an easy to use file compression utility.
Question: I'm having trouble with blocked attachments in Outlook also. How can I fix that?
Answer: Similar to the protection provided through CloudFilter, Outlook blocks dangerous file types and extensions. Visit Microsoft's knowledge base article on blocked attachments for more information.
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