Unable to uninstall

Todd,
We recently installed your plugin for a customer to try out, but they decided to go another route. We’ve tried uninstalling it for them using the WordPress auto-uninstall, which it starts as typical asking if we wish to uninstall all files. We choose the default, and then a blank white page appears with no loading animation in the Google Chrome or Firefox browser tab. We’ve tried leaving it in that state for an extended period of time, up to 30 minutes in one instance. We also tried clearing all browser caches, rebooting MySQL & HTTP services, and ultimately the server, with no change in status. When the admin plugin panel is reloaded, the plugin remains installed and deactivated. Our next alternative is to delete the plugin from the plugin folder, but then we will have to try and find all the settings and data for it that was left in the MySQL database. Would you have some idea why we are getting this behavior and what we might do to resolve it?

http://wordpress.org/extend/plugins/spam-free-wordpress/