3ds Max backup files are created when you save your work in the software. The location of these files depends on your operating system and the settings you have configured.
By default, 3ds Max backup files are saved in the following location on Windows systems:
C:\Users\\AppData\Local\Autodesk\3dsMax\\Backups
where is the account name and is the software version number.
You can change the default backup location by opening the 3ds Max Options dialog and navigating to the Backup tab.
On Mac systems, …