There are two types of symptoms for this issue:

  1. You save a backup to an exFAT partition, no matter on external or internal disk
  2. You boot from Linux-based Acronis Bootable Media or Linux-based Acronis Survival Kit (available in Acronis True Image 2019) and try to browse for that backup
  3.  exFAT partition with backup is displayed, but when you click on it to see the list of files and folders on it, it is shown as empty