When you try to access an FTP site through a web browser, the following error appears:
220 IWSS FTP proxy ready
530 Log in first by USER user@host
The message appears because you are using the IWSS FTP proxy port 21, which is only used for FTP clients. The first line is the standard reply of the IWSS FTP proxy service, while the next line is an error message asking for the authentication credentials.
Internet Explorer, for example, uses the following credentials by default:
Anonymous/IEuser@ when using anonymous FTP
To enable FTP over HTTP, set the proxy to the IWSS HTTP service port, which is 8080 by default.