There is no USENET server at nntp://news.sonic.net
Sonic (and many other ISP) dropped USENET service years ago.
I switched to APN (forte Agent resold. I think it is mostly Giganews) back then. While the rest of the Agent news reader is mostly asleep. APN still provides service.. For how long??
Some groups are available free on http://www.eternal-september.org/
