Cloned disk won't boot to Win7 and Can't access BCD on another disk (the cloned disk)

Craig C

New Member
It's the typical problem where the cloned disk (using Seagate Disk Wizard) won't boot to windows which is normal I guess. It seems straight forward from another post that all I need to do is remove the BCD entry on the cloned disk and then add an entry that should then be then correct for that disk. The guide says I need add a drive letter to the hidden disks but disk management will not do anything with the 100mb EFI system partitions so I can't add a drive letter so I can't see those partitions in windows explorer. I'm assuming that is where the BCD resides (I can't find it). Maybe with EFI you can't modify the BCD on another disk. Is that right?

There is another possible solution I want ask about. I have 3 drives total. The working 500GB mhd, another cloned 500GB mhd (doesn't boot with error to do the repair windows thing), and a cloned 1TB ssd that oddly does boot in a weird way. Instead of getting the error message it looks like it freezes with "Starting Windows" displayed on the screen. I got lucky and noticed the disk activity led would blink once every 15 seconds. I waited and after 5 minutes it booted a little odd without the rotating color balls or the audible jingle but seemed to be working. I installed EasyBCD and as expected the detailed view of the BCD entry looks identical to what I see on the working bootable disk. So, could I just delete the BCD entry with the ssd running and then add another entry that hopefully is now be correct for that disk. If so, what do I select for the drive? My guess is C: but I don't really understand why there is a choice. The running drive has to be C: doesn't it?

Thanks

DiskMangment.jpg
 

Terry60

Knows where his towel is.
Staff member
It gives you a choice because it's usually used to multi-boot OSs, so you need to be able to point to which partition you are referring.
On the working OS, create a repair disc (Control Panel > Backup & Restore > Create Repair Disc) and boot that to fix the BCD on the cloned drive(s) (It contains the repair routines included on the installation DVD)
 

Craig C

New Member
Thanks for the quick reply. Just for clarification:

1) Is this repair disc different or better than the original installation DVD? (I still have it and a copy)

2) So, does this mean you don't think my second paragraph "another possible solution " will work or more importantly will screw things up royally?

3) Maybe with EFI you can't modify the BCD on another disk. Is that right?

I'm not questioning what you're saying, I'm just a little reluctant to use a Microsoft product for a "Hail Mary" type of solution unless I absolutely have to. I don't know what kind of can worms this could open and when I look at the link you reference it gives me more questions.

Thanks
 
Last edited:

Terry60

Knows where his towel is.
Staff member
The Installation DVD will do fine, the repair disc just creates a small subset of it, namely the "repair your computer" option right up front when you boot it.
It's the standard way to fix the BCD on an unbootable PC - perfectly safe and reliable.
(You might need to boot it and "repair" up to 3 times per non-working clone. It only does one thing per pass and there might be several things which need fixing, just be patient.)
It's the best option to straighten out a corrupt (or just wrong) BCD.
EasyBCD works fine provided that you've got at least one bootable OS and you know how to use it to operate on alternative BCDs on BIOS/MBR systems, but the anonymous nature of the EFI System Partition makes UEFI problematic if you're trying to locate a BCD other than the "live" one.
The DVD won't have a problem, that's what it's designed to do.
 

Craig C

New Member
Okay Terry. Thanks a lot for the extra explanation, that makes me feel a lot more confidant. I'm just really paranoid to do a "repair computer" on a computer that is actually working fine, it just doesn't have a good disaster recovery system. I could forget about these clones and look into how windows works for backup, recovery, upgrade disk, etc. I'm also looking for better cloning software that would clone a disk and make it bootable. It looks like Aoemi Backupper makes that claim. Disk Wizard may even do it if I find out how. I'm still thinking of trying my idea with the ssd booted which seems the easiest but the lack of comments makes me hesitate. It would be nice to know why does the ssd boot when the BCD should be "just wrong." It may be some time before I get back with the results but one of these days . . .
 
Last edited:

Terry60

Knows where his towel is.
Staff member
The BCD doesn't contain disk letters, though you see them in EasyBCD.
The partitions are actually addressed using a hash of the unique disk signature and the partition offset from the start of the disk in a clumsy user-error-prone format difficult to read and type. That's stored in a registry partition map, which is where the OS creates virtual disk letters at POST time (unless you've previously personally assigned your own letter using Disk Management, in which case that is also stored in the map and used at POST in preference to dynamic allocation)
When you clone a disk, you also clone the BCD, so the new BCD doesn't point at itself, it points at the drive/partition you cloned it from. That's why you need to "repair" the cloned BCD so that it finds the new unique disk signature and uses that instead of the clone source.
You can achieve the same result by deleting and re-adding a BCD entry with EasyBCD. EasyBCD uses the registry map and finds the disk letter you point it at, and uses the corresponding UID to create the new BCD entry. The disk letters are just EasyBCD translating the near-unintelligible UID into a simple user-friendly letter for your convenience, so though you might think you've done nothing by deleting W7 on "C" and adding W7 on "C", you have in fact created a completely different BCD entry, pointing to the correct drive rather than the clone source. That's also what the DVD repair will do.
Don't worry about "repair your computer". That's just step one. It's followed on the next screen by "repair startup" which is much more specific and exactly what you need.
 

Craig C

New Member
Thanks for the clear concise explanation. I thought that was the way it worked from some of your other posts and this makes it crystal clear.

So, it sounds like what you're saying is if the ssd truly has booted and is in fact the C: drive (seems a no-brainer if C: has 931.29 GB capacity and also disk management says C:=ssd) then removing and adding the BCD should do the trick?

The reason I haven't already done the repair computer is I'm still studying for a permanent or easier plan for my backup/recovery strategy. What I think would be good is once I get the ssd working for the primary working drive, is to clone it to one of the mhd's once a month and alternate between the two. The problem with that is I wouldn't want to be doing a repair computer once a month. I could just not care or even want the mhd's to be bootable, leaving the BCD as it is, so I could boot to a Seagate recovery flash drive that has DiskWizard on it and clone back to the ssd from the mhd which should put the ssd back to the way it was a month ago, if the problem was just a virus or ransomware. If the ssd died then I guess I would have to do the repair.

The thing that really puzzles me is why doesn't all modern cloning software have an option to make the cloned drive bootable to windowns vista and above. If EasyBCD can do it then cloning software could do it too even though then it wouldn't be a true clone but there should be an option. I have a support ticket with Seagate on this. I'll report back.

You say somewhere in this picture is this "hash of the unique disk signature and the partition offset?"

Thanks again.

EasyBCD2_ssd.jpg
 

Terry60

Knows where his towel is.
Staff member
If you just backup your OS and leave the EFI System Partition alone, you won't need to keep repairing.
Partition Managers have multiple options for "copying" a partition, depending on whether it's data or OS. The small print of the manual should point out the differences. The reason why some options don't "repair" the BCD is because you don't necessarily want someone modifying your OS to make it work elsewhere, you want to keep it a 100% bit for bit clone of the original, depending on exactly what you're doing.
As a rule, all partition managers have a Backup/Restore combo, which is generally what you should be using for OS redundancy, rather than the more involved cloning between devices you seem to be opting for.
 

Craig C

New Member
I spent a lot of time reading and outputting some things to try and understand what the problem was before I finally got things fixed, I think.
I found you can see all the details better using this command which redirects the output to the file out.txt. "bcdedit /enum all > out.txt"
You can also see a lot of information about your disks running these commands:
diskpart
DISKPART> list volume
DISKPART> list disk
DISKPART> select disk 0
DISKPART> detail disk
You do the select disk and detail disk for all your disks.

The first thing I tried was, with the ssd as the boot drive, I did the EasyBCD remove entry and add entry. That made some changes to the BCD but not much and it still booted but still took 5 minutes.
Then I disconnected the two mhd's and with only ssd connected did the windows repair CD thing and that made big changes. There was a totally new UID in the BCD. It still took 5 minutes to boot which is more accurately the time it took for the desktop to appear and be usable.
What fixed the long boot time is I moved the ssd cable from port 4 to port 0. I couldn't believe it. I thought there was no difference at all between any of the connectors on the MB. I put it originally on port 4 because it was convenient physically and ports 0 and 1 were in use anyway. It seems weird that all the searching and reading I did for slow boot time there was no mention that gigabyte mb's like to boot from port 0 or 1 and I'm not really sure about 1. My guess is that the only reason it booted at all on port 4 is because of some sort of master/slave thing. I saw this in the device manager that made me think of trying it:
ata.jpg

I think what I will try now is using the built in win7 backup to iso image.
Thanks
 
Top