1. First, after the computer is restored, open the PPT file, and then click the file icon in the upper left corner, as shown in the figure below, and then go to the next step.

2. Secondly, click the PowerPoint option in the file drop-down menu window, as shown in the figure below, and then go to the next step.

3. Next, click the "Save" option in the pop-up window of PowerPoint options, and then copy the path of the default file location in the right interface, as shown in the figure below, and then enter the next step.

4. Then, open my computer, paste the path copied above into the address bar, and press enter, as shown in the figure below, and then go to the next step.

5. Finally, you can see the unsaved PPT file, as shown in the figure below.