You can show any previously hidden objects.
You have activated the navigation mode.
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1. Click on the Show objects button in the Navigation Mode dialog box. The Show objects dialog box displays all hidden objects in the model.
2. Select the objects you want to show.
3. Click OK.
The corresponding objects and connections that lead to visible objects will be displayed.
If you have run navigation mode, you can show and hide objects using the Navigation mode dialog box.