Abstract: The invention provides tools and techniques for running pre-boot code on a computer from a file stored in a file system on the computer. The pre-boot code may include an operating system which is not otherwise installed on the system. For instance, the pre-boot code may be used to boot a DOS operating system on a computer which lacks a DOS hard disk partition. The pre-boot code may contain code to perform operations that are difficult to perform after the operating system is booted, such as code for monitoring the boot process to help debug it. The pre-boot code is obtained from the file without using booted file system code, and is then executed. The code may be obtained by redirecting floppy drive I/O to read the pre-boot code from a copy in memory, or to read it as needed from one or more files on the hard disk.

Abstract: The invention provides systems and methods for storing and recovering images in a computer partition, and more particularly to tools and techniques for placing and extracting images to and from the same partition that is imaged. Both a factory image and a user-updateable image may be stored on the same partition. Copies of a portion of the partition data and/or the system data for the imaged partition can be stored at a specified location within the imaged partition, in a separate partition, or on a removable recovery medium, thereby allowing images to be recovered after disruption of the imaged partition's system data. The image may be stored contiguously or non-contiguously. The image may also be stored as a system file or as an image container which comprises one or more than one image file. To speed restoration time and to assist recovery, the image may be stored at or near the end of the partition. Familiar or novel image formats may be used.