File > New command makes the application ready for new work. The Viewing Window, Feature Tree, Model Tree and so on are initialized.

1.

Select File > New in the menu or click the icon  in the toolbar.

2.

If there is an existing model that was changed, the following save confirmation dialog box appears.

But if there is only simple change such as view rotation, this dialog box won't appear.

3.

To save the changes, click Yes. To not save the change, click No. To quit this operation, click Cancel.