Version 5 of Microsoft's Internet Explorer web browser ("IE5") installs a feature of Windows called Web Folders.
Once you have installed Internet Explorer version 5, depending on the configuration of your Internet connection, you may experience problems doing FTP file downloads from within Internet Explorer.
For example, SPAN files made available for downloading are actually held in directories on the CME's FTP server. You can go to the directory for the CME's SPAN files by going to the web page at www.cme.com/span/spandatx.htm, and clicking on the link for the CME. This attempts to connect you to ftp.cme.com/pub/span/data/cme.
Suppose you do this and the connection doesn't work. For example, it is possible that you will get an error message reading: "FTP Folder Error: An error occurred reading the contents of the folder. Make sure the file name is valid and you have permission to access the location specified. Details: the operation timed out."
If this happens, it probably means that the "Web Folders" feature doesn't work in your environment. This is commonly the case if your company has a direct Internet connection going through a proxy server.
You can probably fix the problem by turning off the Web Folders feature of IE5. Do this as follows:
For example, suppose you are in IE5, and you go to the Web page from which you can FTP site page for downloading the CME's SPAN files at ftp.cme.com/pub/span/data/cme. This displays a list of currently available SPAN files for the CME. You click on a file to download it, and the download doesn't work. For example,