Using BizTalk to send files to an FTP server via a proxy

A client had the need to use BizTalk to send files to an FTP server via a proxy server. There is no place to specify a proxy in the FTP send adapter configuration and there is nothing about how to do it in the BizTalk documentation nor my search on the web come out with any info on that.

After playing with different configuration variations it was found that the following setup will work:

• In the 'Server' field put the IP of the proxy server
• In the 'User Name' put EndTargetServerIP@UserName.

I want to thank Shuki Licht who is the one who did this research and provided the solution.