The media family on device '' is incorrectly formed. SQL Server cannot process this media family. RESTORE FILELIST is terminating abnormally.

Error:

The media family on device ‘<FILENAME.BAK>’ is incorrectly formed. SQL Server cannot process this media family. RESTORE FILELIST is terminating abnormally.

Solution:

Ensure that backup file is good and copied properly.
You can not restore higher version databse Backup in lower version SQL Server.