Where/how can I learn and gain *complete* control of my MBR?

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I can see no reason why Microsoft should/would be expected to accomodate or assist the booting of other systems, but Linux only does that out of circumstantial necessity ... and gets some good PR in return!


In multi-boot Windows systems, or at least in mine, repair disks can really mess things up. I was careful to put my Win2k on "C" (0,0) as my "base system" so its boot would be the simplest to fix, if necessary, but then fixing XP's boot *always* knocks Win7 out of the mix ... and since I do not happen to have my Win7 on my first drive, Win7's boot *cannot* be fixed without doing a complete reinstallation. I have located some software that *might* be able to just fix the boot, but I have yet to burn the disc and try that.

Now, some folks will say to "just run GRUB again" whenever you need to fix a boot, but that absolutely would *not* work in the situation I just described. When XP's or Win7's loader gets messed up, only their own "startup repair" utilities can fix that ... and that is where Linux definitely has some much-better engineering going on. I presently have Mint sitting out out a drive in an area all by itself, and its loader (placed *only* on its *own* partition) could be easily fixed (if it ever gets broken) without any other system being in any way compromised ... and then the third-party software I just purchased could be told to again scan my entire machine and place/add into *one* menu every system found anywhere.

Sure enough!


No problem there. In my limited experience so far, that is a good place to go for help.


CloudWalker and others here have been very helpful at various times over much of the year I have been here, but like you said, "everyone's setup is different , so it's hard to tell, you know?"


I will likely never get away from Windows altogether, but I did just make room for more Linux in my system!

In general, you don't need to fix each version of Windows one by one, you only need to fix the latest version and the Windows boot loader will have the entries of all the other versions of Windows.

What complicated things here as you already figured out is that Win7 is on another partition. But to the contrary to your belief, when your Win7 is working, its boot loader is located on one of the partition on your first harddisk. The BIOS simply will not load a boot loader from the secondary harddisk when there's one in the primary. If your Win7 is working now, run Disk Management, the System partition should be on your primary harddisk, and when something mess up, its this partition that you want to fix. That being said, I think the M$ technician is correct in that the graphical System Recovery of Win7 can't handle this automatically. You have to choose the command prompt instead and run diskpart and possibly bootsect too. I don't think bcdedit is necessary unless you moved around the partitions in linux.

But seriously, do you really need Win2000 on the the primary drive? It may be simpler to swap the cable of the 2 drives and do a Win7 recovery.


My hunch is that your XP and Win7 are using the same partition for their boot loader and that may be what confused GRUB.


I have been reluctant to suggest 3rd party software since I believe they are not particularly useful once you work out the way. Both Windows and linux's boot loader are usually good enough, but tell us how you think about this software after you've some time with it. It's always good to know a piece of good software.

It always puzzle me why some people think that following up an insult with no offense will make it less insulting.

And in case you need a summary of what my points are in this thread:
1. if your setup is sound, you can simply set the partition of an OS to active and that OS will boot, albeit without boot menu
2. to do that in linux, install grub to root not MBR
3. both the Windows boot loader and grub can boot any OS set up this way
4. the only thing left is to add the correct entries to bcd or grub

When the XP loader is broken, Win7 cannot fix it, and fixing XP's loader knocks Win7's out. Win7 can only pick up working loaders, it cannot fix other ones ... and interestingly, Win7 also picks up an extra, non-working link for 98!

My Win7 menu looks like this:

"Previous versions of Windows" (leading to a three-line "boot.ini" menu for 98, 2k and XP)
"Windows 7 Ultimate"
"Windows 98" (resulting in a "press any key to return" error)

And of course, EasyBCD can usually add Linux or whatever else to that.


Yes, I know that. It is in a hidden "Boot" folder on my "C".


Sure, and I have never expected it to do that.


Win7 hijacks the letter "C" and re-arranges my drive order and *shows itself* as being in the first partition on the first drive when it is running, but all of it other than its "Boot" folder is actually located on the last partion ("M") on my last drive.


After Win7's loader has been broken by an XP "startup repair", there is no way to get to any Win7 command prompt. However, and if I have understood correctly, NeoSmart has a link to an iso file for the Microsoft console made available but not packaged with Win7. So, maybe that will do what Win7's installer can do even with Win7 out on the end of my third drive.


Understood.


If it were anywhere else, I would never have gotten this far with this system. Win2k is almost bullet-proof, and it can set things up for all other Windows systems.


Maybe, but I doubt that unless GRUB looks past the boot sector and sees both "Boot" (the Win7 folder) and "boot.ini" (XP) on "C". And yes, as you have suspected, they are both there together.


Sure, but I already know it does not do everything I want. I want to be able to put loaders for each system, including Windows, in separate places and to then call them from wherever else (just like can be done with Linux). As great as Windows might be, Microsoft does not have any management rights over my machine and it has no good excuse for the difficulties encountered even when trying to multi-boot just its own stuff.

No, its Computers, Math, Science, and Technology and an appropriate place for this. And you dont have to read the topic. There is a community of computer aficionados here and this conversation is both germaine and of value to the community.

If I were fussing with such a thing, I would set up an internal usb port, throw in a small flash drive, install my boot loaders there and slide the write protection to the lock position.

Ah, great minds really *do* think alike! That is exactly where I am headed, and the internals are already in place. I think Cloud's last couple of posts offer more information than I happen to comprehend at the moment, but a few more things did "click" just this morning ...

Actually, it would be nice if three or four pages were all it had taken to get this far! I began by learning to multi-boot Win98 and Win2k a couple of years ago, and now I hope to soon put Debian back into this machine alongside the Mint and all the Windows already here. So for me, three or four pages here are but a few drops in the bucket I have been dragging around until things finally began coming together in the third or fourth year!

Please know your input is solicited and welcomed here, and that your flaming of CloudWalker or anyone else is not.

How did you know?!


I need to do some detailed learning about the locations, differences and relationships between MBRs, boot sectors and boot loaders since Windows and Linux do that so differently, but your mention of Win7's "Boot" (system) folder has now begun some defragging inside my mind! Other people were here long before me, of course, but the thrill is mine at the moment.

... and I forgot to mention the very-most-important part of that:

XxClone is indispensible for me -- let the folks there take a bow -- it works perfectly in Win2k and it must be on "C" (system root) to clone same. I have the subscribed version that can do a few extra things, but even the ever-free "test drive" version does just as well at cloning ... and my XxCloned backups have bailed me out more than once when one or another system (mostly XP) somehow got trashed.

Doesn't Win2000 and XP do the same? It's standard practice to use C: for the Boot partition because a lot of programs are hardcoded to it. If your Win2000 or XP is using something other than C: as the system drive, it could lead to all sorts of problems.

Anyway, drive letter in Windows is just short-hand to mount points. The list is stored in HKLM\System\MountDevices. If you are unhappy with the defaults Windows used, just change it in Computer Management. But don't change C: and drives that you've installed programs to.


What I mean is that when you boot from the Win7 DVD, select "Repair your computer", "Use recovery tools...", and then "Command Prompt". It's not that different from recovery console, only some commands have changed.

In the command prompt, you can run "bootrec /FixBoot" to write back the boot sector, and diskpart to set the active partition back to the correct partition. (it's interactive, you have to do something like "select disk 0", "select partition 1", "active", the number depends on your setup)


That looks normal. So "Windows 98" doesn't work. What about "Previous versions of Windows"? Anyway, the manual way to fix boot issue is to run these at the aforementioned command prompt:
bootrec /FixMbr
bootrec /FixBoot
bootrec /RebuildBcd
It will usually let Win7 boot menu find XP again. I have not tried it with XP, 2000, and 98 all together but it's worth a try next time something like this happen.

However, what's actually in my mind is that the damage usually won't go that deep.

Supposed you were using the Win7 boot loader before and somehow a linux distro took over the whole boot chain. What usually happened is that grub has been written to the boot sector and the reserved area after that. The config of the Windows boot loader should be intact. So all you have to do to get back the original menu is to use "bootrec /FixBoot" to write back a normal boot sector and diskpart to set the active partition back. Windows doesn't care about the reserved area so you can leave it as is. All should be back to normal, may be except the linux parition.

The other way around is Windows taking over grub. In this case the boot sector is replaced and the active partition may be changed. grub doesn't care about active partition so that's a non-issus. The grub settings should be intact too but I don't think there's a simple command to write just the part of grub that's in the boot sector. So you either reinstall grub; back up the grub boot sector beforehand and restore it; or put grub in /root or its own partition, so selecting grub back is just changing the active partition.


Yes, that's a great idea.


Looks neat. Just for the record, BootIt Next Generation is a similar program I use. It is also a boot manager but I mainly use the partitioning and disk imaging functions.

No, but I have since realized I was wrong when meaning to say Win7 actually shuffles the hard-drive order. "Disk Management" in 2K, XP or Win7 does always show all drives in their as-installed locations, but Win7 (while running) will hijack the letter "C" for itself if it is not already known that way. I am pretty sure Win7 is set up like that for some overall "security" (file protection) purposes, yet I do find it a bit ironic that any other Windows can do things Win7 cannot, such as run under any drive letter and repair their own startups even when not on drive "0"!


I check for that when installing things, but I do not recall ever having more than just a very few and older programs that were unable to be installed and run under a different drive letter.


I do not think "Command Prompt" is there in my copy, but I will take another look. My OEM XP disk does not have a "Repair Installation" option.


Yes, that is there.

Overall, I know the things you are saying about doing startup repairs to be true, and I believe the majority of the MBR problems I have been having stem from my having a BIOS I do not fully understand -- you and others helped me a lot with that some time ago -- along with the fact my three drives were not all present from the very beginning. Just this morning, however, I let my new partitioner square things around and write a solid MBR. So at the moment, the only known issue here is the matter of trying to find the 2K/XP "boot.ini" file written by that new program's startup manager ... and I suspect it is in that "Stay Out!" zone at the front of my drive. For sure, it is nowhere to be found on any root or in any folder in my system.

If a forum designed for the general discussion of computers, science, math, and technology in the broadest possible way can give specific advice for a particular MBR multiboot problem, it's doing pretty good.

You're right, this isn't the Ubuntu forums. It has a much broader set of topics, and it isn't focused on helping users. If it can actually help people, so much the better, but the purpose is to discuss technical subjects. Technical subjects were discussed. Mission accomplished.

My limited experience on the Debian forum so far has been good, but most "technical" forums I have visited have never been very helpful at all ... and especially since I am not always/usually doing standard or "typical" stuff. But even beyond getting weary of people challenging what I am doing rather than just answering a question (if they even actually have any answer), this place right here is "home" for me ... and even those of us who might not always appreciate everything about each other nevertheless do take occasional showers to keep from stinking the place up for each other!

MBR-control update: KillDisk is running ...

Everything was in good shape and coming right along until I used FDISK to reformat a couple of FAT32s. I had to do that for the sake of my Win98, but it had never crossed my mind that my new piece of management software and FDISK might have a conflict!

But, now I know *exactly* how to put this system together correctly from the very very beginning this next time, and I never could have gotten those answers anywhere else.

Killdisk? So, you decided to re-install everything from scratch? And with three drives? Please keep posting about your adventure. I must say this thread has been very informative. There are many potential pitfall that I now know to avoid if I ever want to setup a multi-boot system like yours.