Creo Layout > References > Fundamentals > PTC Creo Parametric User Interface > The File Menu > Opening Files > About Viewing Thumbnails
  
About Viewing Thumbnails
You can view thumbnail images of files in the File Open dialog box, Creo Parametric browser, Model Tree, and Windows Explorer.
 
• Thumbnails are not displayed for files that you save when saving_model_thumbnails configuration option is disabled and for files that were saved in versions earlier than Pro/ENGINEER Wildfire 5.0. However, thumbnails for such files are displayed, if the files are open in an active session.
• In a non-DRM session, protected files display icons that represent locked files as thumbnail images.
You can view a larger image of the thumbnail in a popup window in the File Open dialog box, Creo Parametric browser, and the Model Tree. If you click in the popup window a 3D preview image of that model is displayed using the Creo View Express or the Creo Parametric viewer. You can zoom, pan, or spin the model in the popup window.
 
* You can enable or disable the display of the popup window using Views > Show PopUp Viewer in the File Open dialog box and the embedded browser or by clicking in the Model Tree and then clicking Show PopUp Viewer. This setting overrides the display_popup_viewer configuration option.