Tools => Check Connectivity

The Connectivity Checker is a tool available in the project editor which allows you to visually check for opens or shorts in your circuit. It is also useful for finding shorts or opens due to subsectioning. When you select the command Tools => Check Connectivity, the project editor enters the connectivity checking mode. Once the checker is invoked, clicking on any metal or via polygon in the circuit highlights that polygon and all the polygons connected to it.

For a detailed discussion about using the Connectivity Checker, please refer to the "Basics" chapter in the Getting Started manual.