Posted by: Brien Posey
In my previous blog post, I promised to address the issue of why Windows Backup works the way that it does in Windows Vista. I’m not going to pretend to know all of the reasons, but I can tell you some of them.
One of the reasons was that NTBACKUP had remained virtually unchanged for many years. It had simply been ported from one version of Windows to the next, and retrofitted whenever necessary. Given the age of the base code, Microsoft had decided that it was time to rebuild the backup application from scratch.
Perhaps a more important reason for the Windows Backup application working the way that it does is that backups are hardware independent. As I’m sure you know, Windows Vista creates backups in .VHD (virtual hard drive) format. Although the virtual hard drives aren’t bootable, they are mountable, which makes it really easy to move data to another machine. It is also really easy to perform a restore to dissimilar hardware, because the backup does not include anything that is HAL specific. In fact, this is one of the reasons why the .VHD files are not bootable.