Spacesurfer's widely referenced post really got me going. That post: http://www.msfn.org/board/Multiboot-Vista-...enu-t95537.html Post #1. Unfortunately that method did not work, because I use System Commander to boot multiple OS's and System Commander uses it's own MBR. The method above replaces that MBR and loses the ability to boot the many OS's on my boot HDD. The boot HDD has 1 primary partition and 1 extended partition with multiple logical drives. The primary partition (system drive) C: is only 900 MB and holds only system commander and the various OS startup files and DOS 6.2 OS's in the extended partitioninclude XPhome, XP pro, Win2000, Vista32, Vista64, PCLinuxOS. After a week of intense trial and error I found a way that works for me and here is the HOWTO: Download grub4dos and unzip to a new folder. Copy grldr.mbr and grldr to the boot © drive Note: we are NOT installing an MBR, merely copying grldr.mbr to the boot (system) drive. The current boot drive MBR is not touched or replaced. Edit boot.ini and add: C:\grldr.mbr="Grub4Dos" to it My boot.ini looks like this: [boot loader] timeout=30 Default=multi(0)disk(0)rdisk(0)partition(11)\windows [operating systems] C:\grldr.mbr="Grub4Dos" multi(0)disk(0)rdisk(0)partition(11)\windows="Windows XP on L ECS" /NoExecute=OptIn /fastdetect /usepmtimer multi(0)disk(0)rdisk(0)partition(8)windows="XP Home on I ECS" /fastdetect /NoExecute=OptIn /usepmtimer multi(0)disk(0)rdisk(0)partition(14)\windows="XP on O ECS" /fastdetect /NoExecute=OptIn /usepmtimer multi(0)disk(0)rdisk(0)partition(13)\winnt="MS Windows 2000 Prof-N" /fastdetect C:\BOOTSECT.DOS="MS-DOS 6.22" /win95dos C:\mixboot.dos="PCLinuxOS" C:\grldr.mbr="Grub4Dos" The 2 copies of Grub4Dos are just for convenience. When you see the boot menu select Grub4Dos and take it from there. I have not been able to make the Grub4Dos entry the default in boot.ini. So select it manually. Anyone have a suggestion here ?. Note that I also boot PCLinuxOS from this. You will have been told the XP bootmgr cannot load non-windows OS's. Not true. If you have a flavor of linux installed, boot to linux and open a terminal. type dd if=/dev/hdaxx bs=512 count=1 of=/mnt/floppy/mixboot.dos where xx is your linux boot partition (hda7) for me and /mnt/floppy is where your floppy is mounted and where the bootsector is temporarily saved. Copy that bootsector (mixboot.dos) to the C drive and add C:\mixboot.dos="PCLinuxOS" to boot.ini Credit for this method goes here: http://www.vsubhash.com/writeups/multiboot_os.asp If that is not enough, one can use bcdedit to add linux to Vista's BCD as well. With easybcd go to add/remove entries, select linux name it and enter the hard drive and partition. That is the tricky part. My linux has separate boot partition located between logical drives D and E. It turns out that HD0 and Partition 4 does the trick. A Linux entry now appears in the Vista boot menu along with Vista, and 'earlier versions of windows'. BTW I don't like that designation so used easybcd to rename it to XP Linux itself is on hda19. It may be possible to go to hda19 directly but have not tried this You can also format a floppy in XP or Vista (do NOT make an MSDOS boot disk) and copy to following to the floppy: folder boot/BCD (create a folder named boot and copy bcd to it) grldr.mbr boot.ini bootmgr grldr mixboot.dos ntdetect.com ntldr This floppy will boot and present the XP boot manager. Select Grub4Dos from the boot menu and take it from there. The floppy boot process is obviously slow and method 1 above is preferred. But do make the floppy. It makes a great recovery disk if the boot HDD is corrupted somehow as Spacesurfer has suggested in his post on how to make that boot floppy