If you set Proxy Settings in Tools->Tool Properties to Use System Proxy Settings when running DbVisualizer on Windows, you may experience problems when trying to connect to a database. The connection attempt may either hang forever or you get an error message that does not make much sense. The reason is that system proxy setting in Windows by default applies to all network protocols, so even attempts to connect to a database go through the proxy. To fix this:

  1. Open Tools->Internet Options in Internet Explorer (or alternatively, in the Control Panel Network Settings in Windows 7)
  2. Open the Connections tab
  3. Click on the LAN settings button
  4. If Use a proxy server ... is enabled, click the Advanced button and disable Use the same proxy server for all protocols

Restart DbVisualizer and try again.