[Plugin: iTunes Affiliate Pro] install fail

Trying to install through the Dashboard plugin installer, and I get this error:

Downloading install package from https://downloads.www.ads-software.com/plugin/itunes-affiliate-pro.zip…

Unpacking the package…

Installing the plugin…

Warning: Invalid argument supplied for foreach() in /www/wendywills.net/htdocs/blog/wp-admin/includes/class-wp-upgrader.php on line 558
The package could not be installed. No valid plugins were found.

Plugin install failed.

https://www.ads-software.com/extend/plugins/itunes-affiliate-pro/