Sometimes the Explorer PaneExplorer in Quadri for Windows disappears. If that happens:

• Exit Quadri for Windows
• Delete the temp directory for storing local layout settings. This is in a directory under %APPDATA%\Trimble\Quadri\XX.YY\Configuration, where XX.YY is the same version number as in the description here: Send Log Files. The directory has the same name as your configuration ("International", "Norway"...). Delete the whole directory.
• Start Quadri for Windows again