Use the changes from (sibling subtask) to display a message to the user when the product version isn't in PAC. The upgrades resource now includes an "unknownProductVersion" in its results that will be set to true or false. If true, display a message something like "This version of <Product> is unknown to the plugin information server. It may be too new to appear, or it may some type of non-standard build. No plugins can be found for unknown product versions."