https://campaigns.f-secure.com/router-checker/ F-Secure Explains Why Router Checker Is Free, Adds Assurance About Privacy http://www.tomshardware.com/news/f-secure-router-checker-dns-hackers,28835.html
I just tested, using an iVPN exit. It's not happy that iVPN's DNS server doesn't accept connections from the Internet, even though it has a public IP address. But that's a feature, not a bug Edit: Maybe that's not the issue. GRC's DNS test says that its fingerprint isn't available. Could that be the issue?