From the developer:
""From Microsoft's knowledge base (Q290497): Outlook 2002 includes a new security feature that blocks attachments considered unsafe. If you receive an e-mail message that contains one of the blocked file types, you may see the following warning message: Outlook blocked access to the following potentially unsafe attachments:
""Although access to the attachment has been blocked, the attachment still exists in the message. The article goes on to explain how to manipulate the registry to allow access to these attachments. This applet does that for you. Simply check the boxes for the file extensions you wish to enable.""