BCDEDIT - How to Use

How to Use the BCDEDIT Command Line Tool​

   Information

This will show you how to use BCDEDIT in the command prompt and avoid the need of third party applications like EasyBCD.

   Note

Bcdedit is a really powerful tool that Windows Vista and Windows 7 uses to manage the boot loader entries.

BCDEDIT needs a boot manager to boot your system.



A boot manager is a file that contains necessary information that instruct the system how to boot/start an operating system.

• Windows 7 and Vista boot manager file is \bootmgr
• Windows XP boot manager file is \ntldr

BCDEDIT can support other boot managers too, like grub for linux. You just have to place the boot file on the root of the boot manager partition. e.g. \grldr and you have a grub boot loader enabled.

Bcdedit edits a file called bcd , which is located in Windows 7's hidden partition under \boot\bcd.
In Vista, its located under C:\boot\bcd.

   Warning

You must be logged on in an administrator account to be able to do this tutorial.

To Use bcdedit:
1. Open an elevated command prompt.

2. Type bcdedit and press enter.
NOTE: By typing just bcdedit you just list your boot entries.


A boot entry consists of 4 main elements:
1. Identifier
The identifier is how the system has named the boot entry.
2. Device
The device is the drive or virtual image that the system will use to boot the boot entry.
3. Path
The path is the location on the device where the bootloader file is found.
4. Description
The description is the friendly name we give to our boot entry, e.g. "Windows 7"
You see next to the identifiers their UUIDs in {}. The UUID is the unique codename that the system gives to each boot entry and cannot be changed.

The standard identifier UUIDs are explained below:
{bootmgr} = the boot manager
{current} = the OS you selected to boot at startup.
{default} = the default OS selected to boot the PC.
{ntldr} = Windows Legacy OS Loader (for windows xp)
there are others like {memdiag} or {ramdisk} but they can't be of much use right now.

   Warning

IMPORTANT: make a backup of your bcd file first. To do that, type:

bcdedit /export C:\SAVEDBCD

This will create a file c:\savebcd which is your boot entry backup.
If you mess up, you can always undo changes by:

bcdedit /import c:\savedbcd

Now to see how we can control the above entries, here are some examples:
bcdedit /set {current} description "My edited Windows Boot Entry"
NOTE: This changes the title of the boot menu entry "{current}".

bcdedit /set {ntldr} device partition=E:
NOTE: This tells bcd that Windows XP partition is drive E:

bcdedit /set {ntldr} path \ntldr
NOTE: This tells bcd that the ntldr file which is the winxp bootloader is on root folder "\" (of drive e: as stated above)

bcdedit /displayorder {ntldr} /addfirst
NOTE: This places Windows XP as the first OS on the menu list.

bcdedit /default {ntldr}
NOTE: This places Windows XP as the default OS to boot first with.

bcdedit /displayorder {33342343-3424-2342342342-2344} /addlast
NOTE: This tells bcd that the boot entry with UUID 3334... should be the last entry on the menu.
You can copy your existing VISTA or W7 boot entry to another identical. Then you can change settings on the new entry to experiment. You will always have the first entry available, so it's safe to play with.
bcdedit /copy {current} /d "New W7 boot entry I just copied!"
this will give you a line:
NOTE: The entry was successfully copied to {4c21825f-e04b-11dd-b760-00195b61617a}. The {4c21825f-e04b-11dd-b760-00195b61617a} is the UUID of the new entry that the system just created. Yours will be different than mine! This is its identifier and you should use this to address that entry. Example:

bcdedit /set {4c21825f-e04b-11dd-b760-00195b61617a} numpoc 2
NOTE: This adds the 2 CPU Core support during boot, like you do in msconfig.

bcdedit /deletevalue {4c21825f-e04b-11dd-b760-00195b61617a} numproc
NOTE: This deletes the numproc parameter from entry {4c21825f....}

bcdedit /delete {4c21825f-e04b-11dd-b760-00195b61617a}
NOTE: This deletes the boot entry {4c21825f....} completely. In order to delete an {ntldr} entry, you must use the /f switch to force deletion: bcdedit /delete {ntldr} /f

You can always type just bcdedit to see your current settings.

What else can I do with BCDEDIT?

You can use BCDEDIT to alter any boot parameter , like you would in msconfig, only more. BCDEDIT works from booting with installation dvd too, so it can be handy for recovery purposes.
bcdedit /timeout 5
NOTE: This sets the wait-to-select-OS menu timeout at startup to 5 seconds . You will notice that I didn't give a UUID above. If you omit the UUID, it applies automatically to the relavant UUID. So: bcdedit /timeout 5 is identical to bcdedit /set {bootmgr} timeout 5
Some more advanced examples:
bcdedit /set {current} detecthal yes
bcdedit /set {current} detecthal no
NOTE: The above commands sets the detecthal to yes or no for entry {current}
To create a new boot entry to load Windows XP from a partition on your disk:
NOTE: The example below uses F: as the Windows XP partition. Replace with your xp drive letter.
bcdedit /create {ntldr} /d "Windows XP"

bcdedit /set {ntldr} device partition=F:

bcdedit /set {ntldr} path \ntldr

bcdedit /displayorder {ntldr} /addlast

   Note

Final note: BCDEDIT works from installation boot dvd too. If you mess up with a setting and you cannot boot, just boot from DVD and enter Repair Computer, then go to command prompt and there you go. You can play again with bcdedit to restore your system back.

Related Tutorials

---

How to Change the OS Name in Windows Boot Manager

 

[Neuro]

I finally realized the problem and solved it.
The original boot configuration has truncated the memory. So via the bcdedit i set the truncated memory value to 4 GB and my pc was reborn.
Thanx for taking the time answering to me.

 

[Brink]

That's great news Neuro. Thank you for posting back with your results.

 

[value]

Hello, by using exactly those commands I added a bootmenu list entry which I want to remove now.

bcdedit /create {ntldr} /d "Windows 71"
bcdedit /set {ntldr} device partition=K:
bcdedit /set {ntldr} path \ntldr
bcdedit /displayorder {ntldr} /addlast

I tried to figure how to remove a entry I created manually by using that list of commands BCDEdit Command-Line Options, but apparently I haven't been able to figure out the syntax of how to remove the entry I created above.

Tyvm.

 

[Brink]

Hello value,

Either option in the tutorial below can help show you how to remove this boot entry. If you like, Option Three is for with the bcdedit command. You would substitute identifier in the command below with the actual identifier displayed for the Windows 71 "description".

bcdedit /delete {identifier}

http://www.sevenforums.com/tutorials/2288-operating-system-start-delete-os-list-boot.html

Hope this helps,
Shawn

 

[williamwclee]

can i use bcdedit to add an SHUTDOWN entry to the boot menu?
if yes, how?

 

[Brink]

Hello William,

I don't believe that's an option.

While in the boot menu, you could safely just press the power button on the case to shut down (power off) the computer if you like.

 

[williamwclee]

Hello William,

I don't believe that's an option.

While in the boot menu, you could safely just press the power button on the case to shut down (power off) the computer if you like.

there is a shutdown option in the advanced boot options menu (shift F8 if it works).

sometimes it is a hard decision to press the power button to shutdown the computer while the hard drive light is still blinking.

 

[Neophile]

Hello,

I have Windows 7 and XP installed on two diferent drives. When I want to make a disk image of Win7with Windows Backup and Restore, it always makes a combined image of both. This is because BCD is on the XP drive, I suppose, but it is very inconvenient because it takes much longer to backup and to restore, and the saved images take up much more disk space.

I followed this tutorial and did exactly what it says, trying to move BCD to the Win7 drive. However, nothing changed about Backup and Restore, and I have two BCD directories, one on the XP drive (where it shouldn't be) and another one on Win7's.

What do I need to do to correct this, please?

 

[milindsmart]

bootmgr is a BOOT MANAGER.

NOT a bootloader. winload.exe IS a boot loader

 

[milindsmart]

Why don't you start a thread of your own? Need a screenshot

But anyway, I suspect it's still using the same active partition. you'll have to choose to boot off the windows 7 drive with the other drive disconnected to truly test that windows is booting completely off its own disk.

 

[jonnyhotchkiss]

Parameters for (Windows 7) BCDEDIT Entries - Critical + Optional

Using native virtualization (VHDs) on Windows 7 (x64, Ultimate).

About to perform clean install - again - to try and fix NVIDIA 'Optimus not working' issue
(2gb Geforce GT540M - GPU load always 0%)

System comparison:

System A: 60 gb. old. lots of problems... but optimus works. terrible performance, attributed to wrecked registry and unoptimised status... looking at bcdedit entry, there is no option for detecthal. is this unusual?

identifier              {c68e3ca4-3b85-11e4-9658-92feb1b9abaf}
device                  vhd=[D:]\vhd\timmy.vhd,locate=custom:12000002
path                    \Windows\system32\winload.exe
description             Timmy!
osdevice                vhd=[D:]\vhd\timmy.vhd,locate=custom:22000002
systemroot              \Windows
resumeobject            {bbed71cb-3b3a-11e4-ac6a-806e6f6e6963}

on most builds I have these options typically...

Windows Boot Loader
-------------------
identifier              {c68e3cb2-3b85-11e4-9658-92feb1b9abaf}
device                  vhd=[D:]\VHD\Jim (TEST!).vhd,locate=custom:12000002
path                    \Windows\system32\winload.exe
description             Jimmy: TESTER!
locale                  en-US
osdevice                vhd=[D:]\VHD\Jim (TEST!).vhd,locate=custom:22000002
systemroot              \Windows
resumeobject            {bc23dd48-8055-11e4-9dfe-806e6f6e6963}
bootux                  Basic
detecthal               Yes

but I've just noticed that Build A (Timmy) - the one with working nvidia config - doesn't have BCDEDIT options that others do, and wondered if this could be preventing NVIDIA GPU from being used


looking at drivers on new builds vs drivers on old no difference - comparing nvidia's system info reports showed that build A has an "nvidia update" entry, whilst all new builds are missing this... also, Build A has an "NVIDIA Drivers" Entry in Programs & Features that isn't present in others...

any insights on BCDEDIT entries and specific intel/nvidia install instructions would be great. contemplating the windows 8 plunge...

 

[dannieboiz]

Hi, is it possible to achieve the following using BCDedit

System has a dual boot, both win 7, 2 partitions

I forgot the password to one of the Win 7 Install so I can't log into it BUT THIS IS THE OS I NEED TO KEEP

From the accessible Win 7, can I use BcEDIT to make the other OS the primary and delete the old one?

don't ask me why I need to do this, it's a long story.

 

[XweAponX]

So for these commands:

bcdedit /create {ntldr} /d "Windows XP"

bcdedit /set {ntldr} device partition=F:

bcdedit /set {ntldr} path \ntldr

I replace {ntldr} with {bootmgr}, or is it a different syntax?