Acronis Backup: warning "drivername.sys not found" during Acronis Universal Restore operation

Symptoms

1. You are applying Universal Restore to a machine. Drivers for Acronis Universal Restore operation are on the bootable media itself or on any external storage, and the bootable media is able to connect to that location, driver files are visible.
2. After Universal Restore starts, you see a message, similar to this:
   Cannot find file 'drivername.sys' that is required for installation of device 'devicename' in Windows Server 2008 R2.