Fix Windows Server 2008 Backup to 3TB External Hard Drive Error

Posted by @Cody

July 29, 2015

Trying to use an 3TB Advanced Format drive (4K sectors) external hard drive for Windows Server 2008 backup location, you may receive an I/O device error. Solutions to fix Windows Server 2008 backup to 3TB external hard drive error.

The Symptom

When using Windows Server 2008 or 2008 R2 snap-in Windows Server Backup tool to backup system to external hard drive with 3TB or larger capacity, you may receive the error messages that The request could not be performed because of an I/O device error (0x8007045D) or other errors.

Backup Failed

The Cause

Because of an incompatibility with Windows Server Backup and 4K sector hard drives, this problem occurs when performing backup to a 3 TB or larger external hard drives that is with advanced format (4K sector size). The Windows 7 and Server 2008 hot fix previously released fixed some issues with these large drives having a 4K sector size, but can not fix Windows Server 2008 backup to 3TB external hard drive error.

The main reason behind is that the built-in backup tool of Windows7, Windows Server 2008 or 2008 R2 will create a .VHD file as the backup image, which can only use 512 byte sectors. Therefore, you cannot create or mount a .VHD file on a hard drive that is advanced format.


In order to fix windows server 2008 backup to 3tb external hard drive error, you have to know that there are basically two types of 4K sector size disks, 4K native, which shows 4 KB as its logical and physical sector size, and 512-byte emulation, which has 512-byte as its logical sector size and 4KB physical sector size. You can run the command “fsutil fsinfo ntfsinfo <drive letter>” to check the hard disk sector size information.

1. Microsoft has officially stated that Windows Server 2008 and 2008 R2 supports Advanced format (4K) disk with 512-byte emulation. The Windows versions which support 512e disks are: Windows Server 2008 R2 w/ MS KB ,982018,Windows Server 2008 R2 SP1, Windows Server 2008 w/ MS KB 2553708. Therefore, if your hard disk is a 512e disk, you just need to upgrade your Server.

2. If your hard drive is a 4K native disk, there is still a workaround to backup Windows Server 2008 to that disk. You can use the WD Quick Formatter tool to emulate 512 byte sectors, but this only works for some hard drives. If you have a WD hard drive, you are lucky. Note that this process will cause all the data on that disk wiped out and other side-effects. You would better backup hard disk before formatting it.

2.1. Install and launch WD Quick Formatter tool.

2.2. Connect only the external hard drive that you want to format.

2.3. Select Most Compatible and click Format Drive to start formatting.


3. If your backup still fails after trying the two steps above, you can whether change your backup drive or upgrade your system to Windows Server 2012, which completely fix the issue with 4K sector hard drive by using .VHDX format to create backup image file.