This software is part of the Linksys product line, which is no longer part of Cisco Systems. It was purchased by Belkin.
If the link is broken in the software suite, you should go to the Linksys forums or contact Linksys support.
Maybe you need to get the latest SmartWifI update utility at
http://support.linksys.com/en-us/support/ccc?
That seems to be the only place that contains the link.
