Acronis Backup for Windows Server Essentials - User Guide - Manual (Page 148)

148 Copyright © Acronis International GmbH, 2002-2014
Limitations
Transferring a Linux system between UEFI and BIOS is not supported.
Transferring a Windows system between UEFI and BIOS is not supported if a backup is stored in any
of these locations:

Acronis Cloud Storage

Tape device

Optical discs (CDs, DVDs, or Blu-ray discs)
When transferring a system between UEFI and BIOS is not supported, Acronis Backup initializes the
target disk with the same partitioning scheme as the original disk. No adjustment of the operating
system is performed. If the target machine supports both UEFI and BIOS, you need to enable the
boot mode corresponding to the original machine. Otherwise, the system will not boot.
5.2.1 Recovering volumes
Let's assume you backed up the system and boot volumes (or the entire machine) and want to
recover these volumes to a different platform. The ability of the recovered system to boot up
depends on the following factors:

Source operating system: is the OS convertible or non-convertible? Convertible operating
systems allow changing the boot mode from BIOS to UEFI and back.

64-bit versions of all Windows operating systems starting with Windows Vista x64 SP1 are
convertible.

64-bit versions of all Windows Server operating systems starting with Windows Server 2008
x64 SP1 are convertible.
All other operating systems are non-convertible.

Source and target disk partition style: MBR or GPT. System and boot volumes of BIOS platforms
use MBR disks. System and boot volumes of UEFI platforms use GPT disks.
When selecting not initialized target disk for recovery, this disk will be automatically initialized
either to GPT or to MBR depending on the original disk partitioning style, the current boot mode
(UEFI or BIOS) and the type of operating systems (convertible or non-convertible) that are
located on this volume.
If the initialization may result in bootability loss, the software takes the partitioning style from
the source volume ignoring the target disk size. In such cases, the software can select the MBR
partitioning style for disks whose size is more than 2 TB; however, the disk space beyond 2 TB
will not be available for use.
If required, you can initialize the target disk manually by using the Disk management (p. 263)
functionality.
The following table summarizes whether it is possible to retain the system bootability when
recovering boot and system volumes of a BIOS-based system to UEFI-based and back.

A green background means that the system will be bootable. No user action is required.

A yellow background means that you need to perform additional steps to make the system
bootable. These steps are not possible on some machines.

A red background means that the system will not be able to boot due to BIOS and UEFI platform
limitations.
Original Target hardware