With regards to the TS Updater program, this can happen for one of two reasons. Primarily, it is because the TeraStation you're looking for doesn't need updating, as it's already running the latest firmware. If you're certain that it's not running the latest firmware, the presence of a software firewall on your system can lead to these symptoms as well. If you're running any kind of "security" applications, try disabling them and then running the Updater again. The NAS Navi is also susceptible to being blocked by firewalls, so treat it the same way.
In some cases, setting the programs for Windows 2000 compatibility mode can help as well. You can do this by right clicking on them, and selecting Properties, then choosing "windows 2000" in the compatibility menu.