Backup fails when you try to create a system image

This article provides a solution to an issue where backup fails when you try to create a system image.

Applies to:   Windows 7 Service Pack 1
Original KB number:   2696906

Symptoms

Consider the following scenario:

  • You are running Windows 7 Service Pack 1.
  • In the Backup and Restore Control Panel applet, you click on the link to "Create a system image".
  • The source volume that you are imaging is 2 terabytes in size or larger.

In this scenario, after the backup process has started, you may see an error similar to the following:

The backup failed.

Volumes larger than 2088958 megabyes cannot be protected. (0x807800B4)

The only option is to close the dialog box and exit out of the Create a system image wizard.

Cause

When creating a system image in Windows 7 Service Pack 1 by using the Create a system image wizard, a virtual hard disk (.vhd) is created and the system image is written to it. The current virtual hard disk specification limits the size of a virtual hard disk to be 2040 GB, which can fit a volume size of 2040 GB - 2 MB (that is, 2088958 MB). Due to this limitation, the source volume size must be 2,088,958 MB or less for the system image to be created.

Note

All of the above values are slightly under 2 TB in size (2 TB = 2048 GB = 2097152 MB).

Resolution

To work around this limit, shrink your volume size to 2,088,958 MB or less prior to creating the system image. More information on shrinking a basic volume can be found in the following article:

Shrink a Basic Volume