The "Always ask before opening this type of address" issue

We’re rolling out a new version of Internet Explorer for a customer.  They were on IE6…

During the pilot, they reported this issue.
Attachment_Manager_Caused_Prompt

The error about is actually generated by a Windows feature called the "Attachment Manager".

"The Attachment Manager in Windows can help protect your computer from unsafe attachments that you might receive with an e-mail message and from unsafe files that you might save from the Internet."

It seems I had gotten two things wrong.

  1. failed to configure the corporate internet address as being in the "Intranet" zone.
  2. failed to configure the Attachment Manager at all.
        Low_file_types

So about that Attachment Manager.
The group policy to configure Attachment Manager can be found in System.Adm.
I created a Attachment Manager only ADM file, which you can download here.

Some reference articles:
Description of how the Attachment Manager works in Microsoft Windows
How To Configure Trusted Sites In Internet Explorer For A Group Policy
Why don’t the file timestamps on an extracted file match the ones stored in the ZIP file?