BOOT.TXT last update by Roedy Green 2009-03-11 Purpose ******* BOOTSAVE and BOOTREST protect you in case you accidentally damage your hard disk master boot sector. BOOTCHK checks if any damage has been done. In the master boot sector is stored the code that gets your machine going when you first power it on, the partition table of how big your various partitions are, and in some cases it contains information about disk geometry (heads, cyls etc). Protects against damage to the partition table or boot sector done by rogue programs, viruses or accidents with tools like Norton NU. This version does NOT save the boot sectors for each partition, ust the master boot sector. The most important thing to remember about BOOTSAVE is that you must recreate your BOOT.SAV file any time you change you hard disk, or change your partitions. Never restore a BOOT.SAV file if you have failed to do this. To be safe, redo your BOOT.SAV any time you change your CMOS. In theory this should only be necessary if you change the disk settings. How Do You Use It ***************** Insert an system DOS-formatted floppy into A: then type: BootSave A:\Boot.Sav It will then create a small file called Boot.Sav in the root directory of your floppy. This contains 4 bytes of information about your disk geometry followed by a 512 byte image of your master boot sector. The geometry information is used to prevent you from accidentally restoring the boot track from one machine onto another machine with a different type of disk. You may also store this file or hard disk with: Label the disk with the name of the machine it come from. If later you suspect the master boot sector may have been damaged on contaminated, boot from a floppy and insert a floppy disk containing the file BootRest.Com and the file Boot.Sav. Then type BootRest A:\Boot.Sav You will then have to reboot before the corrected parameters take effect. In your autoexec.bat file you can put: BootChk C:\CMP\Boot.Sav /Q If errorlevel 1 GoTo Trouble To check that the boot sector has not been tampered with. The /Q option suppresses all but the most crucial messages. Why Use It ********** You may accidentally clobber your boot track of your C: hard disk which contains the MBR (Master Boot Record -- the code that is used to start your computer, and the master partition table which describes the position and sizes of your four main hard disk partition). If you have done a BootSave, you can have it back in minutes. Otherwise you will lose the entire contents of your hard disk. You may accidentally fool around with FDISK and wreck your paritions. BootRest can put the partition table back the way it was. This may rescue your data. A buggy program might accedintaly overwrite your boot sector. A virus might infect your boot sector. BootRest will get rid of it. Windows might destroy your multi-boot to other operating systems such as Linux. Bootsave will easily restore it. YOU MUST USE REAL DOS ********************* A DOS box/window/compatibility box/penalty box/command prompt is not the same as DOS. It is a DOS emulator part of Windows with many features of DOS blocked to enhance the security of the computer. Microsoft rightly considers meddling with the boot record a potentially dangerous thing to do, and block programs running in the DOS box from doing it. For BOOTsave/BOOTrest, you need real DOS, e.g. booting from a DOS floppy, not just the DOS command prompt. GETTING THE LATEST VERSION ************************** Look for the latest version at my Web site: http://mindprod.com/downloads Trouble Shooting **************** > I used BootRest, but it complained the disk geometry was wrong. You probably did BootSaves from several different computers. You then failed to label the disks and used a disk from the wrong computer. You must use the disk that was done on the computer you are trying to rescue. BootRest checks that the number of heads and sectors etc of the disk you are restoring to matches the disk the BootSave was done on. If for some reason the INT 13 is giving the wrong geometry BECAUSE the boot sector is gibbled, you have a Catch-22 situation. In that case, you could modify the BootRest code by putting a semicolon in front of the CALL CHECKGEOM to turn it into a comment, and reassemble. This would be dangerous, so I am not making this easy on purpose. > I accidentally reformatted by hard disk with FORMAT C: without > the /S. I used BootRest, but the C: partition was still unbootable, > and command.com, IO.SYS and MSDOS.SYS were still missing. > None of my files came back either. Your stupid program doesn't > work! BootRest saves only one tiny 512 byte sector near the start of your disk. This is the only thing it can repair. The current version does not even save the boot sectors on the front of each partition. If you want to make your C: partition bootable again, use Norton NDD 4.5 or DiskTool 6.0. You can also try booting from floppy and typing SYS C:. To recover from massive losses of files, there is no subsitute for a tape backup system with daily backups. Perhaps in a future version I will save all boot sectors for each partition. This job is complicated by the extensions that SpeedStor and Ontrack Disk Manager make to the partition table. >I crashed by disk without making a BOOTSAVE file first. What >can I do now? BOOTSAVE is prophylactic. It is useless for correcting trouble if you have not used it PRIOR to the trouble. You may be SOL, but things you can try are: FDISK /MBR and the Norton Utilities Disk Doctor, which may be able to recreate damaged boot sector. Author ****** BOOTSAVE, BOOTREST and BOOTCHK are copyrighted but may be freely used for any purpose except military. If you pass the files on, PLEASE PASS ON THIS DOCUMENTATION TOO. Please report bugs and problems. Freeware Status **************** BOOTSAVE BOOTREST and BOOTCHK are freeware. Roedy Green Canadian Mind Products #101 - 2536 Wark Street Victoria, BC Canada V8T 4G8 tel: (250) 361-9093 mailto:roedyg@mindprod.com http://mindprod.com -30-