As I've said, I can't reproduce the error, tried several points after your report, and they are all working fine. And, nobody every reported this problem before so, it must be some kind of security setting related to the internet connection that must have gone wrong in your system.
Changing the default browser won't change anything: XPOI doesn't start your browser, it uses the Windows internal browser libraries to use its own browser window that relies on the windows Internet Explorer engine so, apparently, something in your system ( security settings or security software or a firewall ) is causing this. Maybe you have some picky firewall that doesn't allow connection, because to it, XPOI is seen as a "foreign" browser, so it blocks it by default.