No Operating System Options at boot

FreeBooter said:

Did the both command find the both operating system and did you ad them to BCD?

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FreeBooter said:

You use bootrec /rebuildbcd command to add those found operating systems to BCD store.

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FreeBooter said:

You use bootrec /rebuildbcd command to add those found operating systems to BCD store.

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FreeBooter said:

You can manually delete and create BCD store file.

If rebuilding the BCD store doesn't resolve the startup issue, you can export and delete the BCD store using this guide.

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suatcini54 said:

bcd store is in EFI\Microsoft\Boot directory.

First assign a letter (Example S:) to EFI system partition and then give the command

attrib S:\EFI\Microsoft\Boot\bcd -h -r -s to relieve the hidden, readonly and system attribute.

and then try to rename it. Then recreate the bcd store using bootrec /rebuildbcd command from Recovery Console.

Hope this helps.

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glasskuter said:

Not my level of expertize so this is not an answer to your question, but I would consider your second sreenshot may be a clue.
The boot configuration data store could not be opened. There is not enough space on the disk.

Either way, IMO disk 2 partition layout is a mess.

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tecknot said:

I got a problem when entering the command "bcdedit /export C:\bcdbackup. I got the response: "The Store export operation has failed. There is not enough space on the disk."

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That new error is an important clue. It reinforces the suspicion that OP's Boot Configuration Data (BCD) store or EFI System Partition (ESP) has a problem, but it doesn't prove that the EFI partition is full.

The command:

bcdedit /export C:\bcdbackup

doesn't simply copy a file. It asks Windows to export the system BCD store. Since bcdedit already failed to open that store, it's not surprising that exporting it fails too.

I would advise OP to stop trying to export or rebuild the BCD until the actual problem is identified. Repeatedly running bcdboot or bcdedit /export won't help if the underlying store cannot be accessed.

What I would tell OP to do next

First, check the free space on C::

fsutil volume diskfree C:

The screenshot shows approximately 780 GB for C:, so it is unlikely to be full, but this verifies that.

Next, from an Administrator Command Prompt (not PowerShell), assuming S: is unused:

mountvol S: /S
fsutil volume diskfree S:
dir S:\EFI\Microsoft\Boot /a
bcdedit /store S:\EFI\Microsoft\Boot\BCD /enum all

These are diagnostic commands, not boot-repair commands. They will help determine whether the EFI partition has adequate space and whether its BCD store can be read directly.

Because OP has several EFI partitions, I would also request:

diskpart
list disk
list volume
exit

This helps identify the mounted EFI volume.

One particularly important possibility: Windows 11 is successfully booting from one EFI partition, but BCDEdit is attempting to access a different or invalid system store. The multiple EFI partitions make that worth investigating.

If the explicit /store command succeeds while ordinary bcdedit fails, that would be a significant clue pointing toward system-store selection rather than simply a full partition.

For now, I would not advise OP to run bcdedit /import, format an EFI partition, or delete any boot files.

Bottom line: The failed export adds evidence that Windows cannot properly access its default BCD store. The next step is to identify the EFI partition Windows is actually using and measure its free space, rather than attempting further repairs blindly.

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suatcini54 said:

Can you do this ?

Boot to Recovery environment and format EFI system partition in FAT32 file system, to start fresh. You should first assign drive letter to EFI system partition S: before formatting.

Then find your Windows partitions and note drive letters and give the command first for your working Windows partition, assume D: is the drive letter when you run vol command in diskpart from Recovery console.

bcdboot D:\Windows /f UEFI /s S: /bootex ( D: is your working Windows partition. Change drive letter to suit your system )

Then you can add the other Windows installations

bcdboot E:\Windows /f UEFI /s S: /bootex ( E: is your other Windows partition. Change drive letter to suit your system )

Hope this helps.

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glasskuter said:

"The boot configuration data store could not be opened. There is not enough space on the disk." typically occurs when the EFI System Partition (ESP) or reserved boot partition has run out of free space, is corrupted, or lacks proper file system formatting/drive letters during recovery mode.

We've seen bcd problems before when 100mb EFI is not large enough to store the bcd.

I remember some of your other threads and I was unable to follow what exactly you had tried to do that got you where you are.

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suatcini54 said:

Your EFI system partition size is 2 GB. Right ? So there should be enough space unless you have filled it with some big files. You do not have any other EFI partitions. You have several 100 MB partitions. But they are not labeled EFI.

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suatcini54 said:

If you want to dual-boot or triple-boot, you need one EFI partition. And in fact, you have one EFI partition. You should use that.

If you reformat that EFI partition, you make a clean start. After that you use bcdboot command as I had given above for your working Windows installation. Drive letter for your working Windows must be determined when you run diskpart from recovery console.

After that you must reboot into your working Windows to make sure you have a working OS.

Then you can use bcdboot to add other Windows installations using their partition drive letters.

If you do not want dual-boot, you can have separate boot for each Windows installation. But then you must boot into BIOS to choose and your other Windows installations. The following screenshot is from my system.

...
I have two Windows installations and two EFI system partitions. I can boot into an OS by choosing it in BIOS. I can make any OS default OS and it automatically boots each time I power on my PC.

Hope this helps.

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