Use 'Options/Folder tree' submenu to enable the folder tree.
WinRAR can display the folder tree panel allowing to navigate in disk and archive folders. Multithreading is enabled by default, but you can disable it in 'General' part of 'Settings' dialog. Multithreaded version of RAR compression algorithm improves the compression speed on computers with several CPU, dual core CPU and processors with hyperthreading technology.
