Triple-boot on 2 disks -> dual-boot on 1 disk

Paramaibo

Member
Last year I had a dual boot 7 with 32bit and 64bit, and unknowingly installed the 32 first and 64 thereafter (on 2 partitions of SSD). I realise now that I want to delete 32bit and cannot format this partition.

I ask because I have a Win 10 partition on my HDD that I eventually want to clone to the SSD and thereafter only have 2 partitions with 64bit 7 & 10.

I have since read Terry60's comment on a similar thread:
"You can't boot a newer Winload from an older Bootmgr.
Compatibility is backward, not forward.
Boot your W10 and add a W7 entry to the newer BCD.
Alternatively, if your W7 is on a faster device and you want to boot that way round for performance reasons, you'll need to rename W7's bootmgr and drag a copy of W10's (bigger) version across alongside it, so that the bootmgr will recognize the dig sig of Winload
."

This news further complicates matters and I wonder whether anybody can help.

SDD
SSD.JPG

HDD (with no other OS)
HDD.JPG
 
If that's a working triple-boot, then you already have the W10 bootmgr sitting in the x86 partition (It will take control of the active partition and replace bootmgr as part of the install process) so you don't need to do anything about that.
It should be a straightforward process, were it not for the logical drives you have chosen to use.
A logical drive cannot be active so cannot contain boot files, so you can't move the boot files to either OS to free up your D partition.
I can see that you've not included your whole HDD/SSD configuration, so I don't know what other primary partitions (if any) are available.
Assuming you have one somewhere, you can use EasyBCD
https://neosmart.net/forums/showthread.php?t=12890
to copy the boot files from D, then switch the BIOS (if necessary) to boot from the new location.
When you have verified that the triple boot works from the new boot drive (it will show as "system" "active" instead of D) you can format D, clone W10 across, then use EasyBCD again to copy the boot files back again into W10's now primary slot on the SSD and switch the boot priority back to that drive.
Don't worry about
https://neosmart.net/forums/showthread.php?t=12890
it doesn't alter the working boot at all, merely copies everything necessary to the new location, so you can always fall back to the status quo ante if anything about the copy should fail.
 
If that's a working triple-boot, then you already have the W10 bootmgr sitting in the x86 partition (It will take control of the active partition and replace bootmgr as part of the install process) so you don't need to do anything about that.
It should be a straightforward process, were it not for the logical drives you have chosen to use.
A logical drive cannot be active so cannot contain boot files, so you can't move the boot files to either OS to free up your D partition.
I can see that you've not included your whole HDD/SSD configuration, so I don't know what other primary partitions (if any) are available.
Assuming you have one somewhere, you can use EasyBCD
https://neosmart.net/forums/showthread.php?t=12890
to copy the boot files from D, then switch the BIOS (if necessary) to boot from the new location.
When you have verified that the triple boot works from the new boot drive (it will show as "system" "active" instead of D) you can format D, clone W10 across, then use EasyBCD again to copy the boot files back again into W10's now primary slot on the SSD and switch the boot priority back to that drive.
Don't worry about
https://neosmart.net/forums/showthread.php?t=12890
it doesn't alter the working boot at all, merely copies everything necessary to the new location, so you can always fall back to the status quo ante if anything about the copy should fail.
Hi Terry, I've been busy for the last couple of weeks and let this linger.

I've made C a primary, simply by booting into H (Win 10) and changing it from logical to primary. I repeated the process with H and the entire system looks like this in Easeus:Disks.JPG

and this in Windows, where H is logical:
Disks Win.JPG

Is there a way now to move boot files so that I can eventually end up with the desired configuration?
 
I now have:

Disks now.JPG

and Win 10 doesn't boot; however it didn't do so just before the resizing/moving of partitions when I copied the boot files with EasyBCD. Now, as then, the black screen instructs me to insert the installation disk and perform a repair, though I don't have a Win 10 installation disk.
 
In my original reply, I started "If that's a working triple-boot..."
If W10 wasn't booting, and the boot failure was "invalid digital signature" or words to that effect, then you have fallen foul of "can't boot a newer from an older"
All you need to do to fix that in the absence of an installation disk is copy the W10 version (392kb) of bootmgr to replace the W7 version (375kb).
You'll find a copy in \Windows\Boot\PCAT, and it will need to be copied directly into the root of the "system" partition (i.e. C:\bootmgr )
 
The triple-boot was working, up until I deleted the 32 partition and did precisely what you advised above. This is the case now again, once I performed "change boot drive" with EasyBCD with C as the target drive.

In the meantime, I had downloaded a win 10 iso and attempted a repair of the installation where I had two entries and win 10 would start on Blue Window boot screen and "serrated circle spun" a few times before giving up the ghost with the screen going black but remaining illuminated and arrow cursor moveable. It now starts filling up the unallocated space; it is hard to know what is happening as only the usb blinks and win 10 tells you nothing.

When I tried to copy the win 10 bootmgr was, as now, 387kb and win 7 is 375kb. I naively thought that I could simply extract the bootmanager from the iso, while within one of the the two OS left standing.

Visual BCD offers a whole lot of options and details, that could possibly be informative had I known what they meant in practice.
 
For instance, were I to edit the bootmgr entry to D instead of C, would that be another way ensuring that the newer bootmgr was used in the process?

I currently boot with 10 as the default and have tried all the start-up tools on offer, those these only lead me to a dark illuminated screen with a moveable cursor.

Yesterday, I did an offline sfc and it keeps on recurring at various times when I reboot & that's getting quite irritating too.
 
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and did precisely what you advised above
Not quite.
When you have verified that the triple boot works from the new boot drive

If you'd copied the boot files to a primary partition without altering anything else, you could always have reverted to the previous situation.
Did you verify that W10 booted from the new copy of the boot files before you either altered W10's partition with Easus, or moved it to its new location and overwrote the original boot files?
If not, we've no idea which of the 3 actions has caused W10 to stop booting.
If bootmgr is bigger than 375k it would already seem to be one of the iterations of W10's version, so the failure to boot is probably related to the move of the OS from one location to another.
The information in the BCD has no "letters". The BCD locates things with a hash of the unique disk ID and the partition offset. EasyBCD translates those into a "disk letter" when communicating with you, because the coded information is unintelligible to mere humans.
The BCD information relates to where W10 used to be. As you've moved it, bootmanager is attempting to find Winload in the wrong place.
You should simply be able to correct that by deleting the W10 entry from the BCD and adding it again.
Point it at the disk letter of W10 in it's new position as seen from the booted OS (W7).
EasyBCD also does the translation the other way round and will convert your disk letter into the correct UID hash using the W7 registry to look up where W10 really is now.
 
I used EaseUS to recover the lost boot partition and have copied it to the SSD. Is there a way to point the win 10 OS to these orphaned files before hiding the partition?

Disk 1.JPG
 
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In my incremental progress of sorts, w10 now boots but fails to reach the login screen (requires manual shutdown). I have waited 7-8 minutes but nothing happens. I prefer w7's operation for the simple reason that you are provided with visuals signifying progress or otherwise. This does not occur in w10 where, had it not been for the blinking light on the USB, I could easily have assumed that the boot screen had frozen and the process should be aborted; it is also far slower than w7 in offline mode.

There is no safe mode yet.

Have done startup repairs with both w7 & w10 USBs & also bootrec cmd lines and offline USB Macrium boot fix and EasyBCD now looks like this
EasyBCD.JPG

VisualBCD looks like this

VisualBCD 1.JPG VisualBCD 2.JPG VisualBCD 3.JPG
 
Wow, talk about a temperamental OS!

More to the point though, how does one access the registry through cmd lines in USB start repair? I guess I make an image of the OS as is, to substitute for backing it up; but that is as far as my limited imagination stretches.

Thanks a lot Terry for digging up this obscure little detail that so far has offered a possible way forward, after I had imagined all further avenues had been exhausted.
 
Not if it's a disk letter change.
iirc with Vista onwards, the boot hang happens at a point where it is possible to get into regedit but it's been many years since I last had to fix such a problem.
It is possible to load the registry hive from the dead system using the one that's working though it's not something I have dome myself, but a web-search will probably yield instructions.
 
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