Unknown hostname abc.net

After upgrading TSVN to 1.2.0 from 1.1.7, when I do an update I get "unknown
hostname abc.net". Uninstalled 1.2.0 and reinstalled 1.1.7 and all is well.

Some firewall programs detect program changes and silently disallow access to the network. In this case, fixing ZoneAlarm's settings for TSVN solved the problem.