Abstract: Method for booting from a backup, including loading an initialization application that identifies a storage with a backup; activating a handler of a BIOS interrupt module, for intercepting boot loader requests to the storage, and for redirecting them to the backup; creating a bitmap of the blocks in the backup and of a writable storage device to which new data will be written; initiating the BIOS to load and execute boot blocks from the backup; transferring control to a routine defined by a boot record in the boot blocks; activating an I/O filter for intercepting requests to the writable storage device; for write requests, the filter writes a corresponding block to the writable data storage, and marks this block in the bitmap; for read requests, the filter checks the bitmap if this data block was unchanged, and redirects the read request to the backup, otherwise, the filter redirects the read request to the writeable storage device.