All good day, tell me how to restore a PPT file, if there is such an error message: the file may be corrupted or the file type is not recognized in PowerPoint format.?

To resolve the above error message, follow the below mentioned steps:

1. Click File, then choose Save As.
2. Save the PowerPoint file at a new destination with the same or a new name.
3. or you can try to use power point repair , find here - http://www.powerpoint.repair/