How to force "FTP" action to work though proxy server?

[kinook]

Here's the response from the vendor of the networking component we use for FTP:

The ISA Server doesn't implement an FTP proxy per se, only an HTTP proxy that also handles FTP requests. When you normally enter an ftp:// URL in IE, the browser will use FTP to retrieve the file. However, when you setup IE to use a proxy, that ftp:// URL is passed to the proxy server and the proxy performs the download and then returns the contents to the client. In that case, the browser actually sees it as an HTTP GET request. I know that sounds odd, but that's how it works.

In short, you don't need to use proxy settings in the FTP control with ISA Server, you just connect normally. However, presuming that ISA Server is your gateway and also acting as your firewall, you need to have it configured to allow outbound FTP connections and the control itself should be set to use passive mode transfers.