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I have a "Recovery" partition which I mistakenly thought was redundant after reinstalling everything to C:. "Recovery" was previously the "Active" partition. I set C: as the "Active" directory in disk manager (I am using Windows 7). When attempting to boot, the laptop now returns "BOOTMGR is missing".

I can go to BIOS and mess around with some stuff, but haven't found a way to change the active partition. I can disable various SATA drives (four are listed) and doing that sequentially changes the error message on booting, but no combination lets it boot.

I am travelling and don't have a USB key or bootable CD with me. I do have an external HD, but this other computer that I'm on right now (which is unusably slow) doesn't recognise it.

I think that the easiest solution will be to get hold of a USB key, make it bootable, and sort out the active partition from DOS. Any glaring shortcuts, alternative solutions or likely obstacles I'm missing?

Edit: I now have a USB key, can boot to DOS and run fdisk, which I expected to enable the active partition to be set. Unfortunately fdisk will not set NTFS partitions as active, and I haven't found any alternatives that run from DOS and will set NTFS partitions as active. At this stage it looks as though I will need to get Windows CDs as Olivier mentioned below.

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That's probably the best method or installing the boot loader to the drive instead of any partition (which I believe is almost always done by default on windows). But again, that requires either a USB or CD. Either of which are nearly universally available nowadays (gas stations even have low end flash drives oftentimes). In the bios, have you checked that the correct drive is the default boot option? A bit more risky is popping out the C drive putting it in another box (maybe using the external enclosure) and fixing there. –  nerdwaller Feb 23 '13 at 20:42
Yes, the correct drive is the default boot option. For that matter I have tried changing the order and nothing unexpected / promising seems to happen. Thanks nerdwalker –  Levi Feb 23 '13 at 21:47
Does your laptop have a network boot option? You might be able to get what you need from the other computer. –  Radoo Feb 24 '13 at 0:04
I am not sure whether my laptop has a network boot option. There is nothing obvious listed in the bios. I've been searching for half an hour and not found clarity (partly because it takes a minute or two for each page to open on this other computer). Heading out to get a USB key now. Thanks Radoo –  Levi Feb 24 '13 at 9:56

5 Answers 5

up vote 3 down vote accepted

In the end I solved this by creating a bootable USB with the Windows ISO on it, and ran the "Repair" tool twice.

I essentially followed the instructions at: http://en.community.dell.com/support-forums/software-os/w/microsoft_os/3316.2-1-microsoft-windows-7-official-iso-download-links-digital-river.aspx

  • In my case, I was using Windows 7 Professional (x86), so I downloaded that ISO.
  • Then I used the "Microsoft USB/DVD download tool" to create the bootable USB.

Many thanks for the help.

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In case that you only have windows, you have to boot from a cd. There is no other option, I have searched a lot for other options but they don't exist.

The only other option to solve problems on Windows is to press F8 by booting and opening a recovery console, but it won't work in your case.

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Thanks Olivier, I do only have windows, have searched a lot as well and appear to be heading in the same direction. I will provide an update if I can get an alternative to work. –  Levi Feb 24 '13 at 20:04
Hi Olivier, in the end I booted from a USB with the Windows ISO on it, which I think is essentially the same. –  Levi Feb 25 '13 at 12:26

There are a number of possible causes for BOOTMGR errors, including the most common "BOOTMGR is missing" error message.

The most common reasons for BOOTMGR errors include corrupt and misconfigured files, hard drive and operating system upgrade issues, corrupt hard drive sectors, an outdated BIOS, and damaged or loose IDE cables.

Anothe reason you might see BOOTMGR errors is if your PC is trying to boot from a hard drive or flash drive that is not properly configured to be booted from. In other words, it's trying to boot from a non-bootable source. This also would apply to media on an optical drive or floppy drive that you're trying to boot from. Fixes for BOOTMGR Errors

  1. Restart the PC. The BOOTMGR error could be a fluke.

  2. Perform a startup repair of Windows. This type of installation should replace any missing or corrupt files, including BOOTMGR. Continue troubleshooting if this does not resolve the issue.

  3. Check your floppy and optical drives for media. Often times, the "BOOTMGR is Missing" error will appear if your PC is trying to boot to a non-bootable floppy disk or CD/DVD. Note: If you find that this is the cause of your issue and it's happening regularly, you might want to consider changing the boot order in BIOS so the hard drive is listed as the first boot device.

  4. Check the hard drive and other drive settings in BIOS and ensure they are correct. The BIOS configuration tells the computer how to use a drive so incorrect settings can cause problems, including BOOTMGR errors. Note: There's usually an Auto setting in BIOS for hard disk and optical drive configurations which is usually a safe bet if you're not sure what to do.

  5. Reseat all internal data and power cables. BOOTMGR error messages could be caused by loose or malfunctioning power or controller cables. Try replacing the PATA or SATA cable if you suspect it might be faulty.

  6. Update your motherboard's BIOS. An outdated BIOS version can sometimes cause the "BOOTMGR is Missing" error.

  7. Perform a clean installation of Windows. This type of installation will completely remove Windows from your PC and install it again from scratch. While this will almost certainly resolve any BOOTMGR errors, it's a time consuming process due to the fact that all of your data must be backed up and then later restored. If you can't gain access to your files to back them up, please understand that you will lose them all if you continue with a clean installation of Windows!

  8. Replace the hard drive and then install a new copy of Windows. If all else has failed, including the clean installation from the last step, you're most likely facing a hardware issue with your hard drive. BOOTMGR Errors Apply To BOOTMGR issues apply to Windows 7 and Windows Vista operating systems only. Windows XP does not utilize BOOTMGR. The equivalent function in Windows XP is NTLDR.

PS: there is also a "no windows cd way : /rebuild BCD /scanos /fixmbr /fixboot

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The active partition is the partition which the system will use to boot from. In your case, you've changed it so that the required bootmgr could not be loaded. You need to set the partition named 'Reserved by system' to active. This partition usually has no letter assigned to it. You can set this with a bootable live USB running a partitioning program. Below I've placed a link which describes how to make such a live USB running easeUS:


After you do this, everything should work again.

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Thanks Jochem. I had tried several partition programs, and couldn't find one that both worked from DOS and allowed me to change the active partition on the hard drive. The problem is now solved for me (I am about to type up the solution I used), so I won't try the tool that you suggested. Hopefully it will save someone else some time. –  Levi Feb 25 '13 at 12:25
@levi Good to hear it's solved –  Jochem Kuijpers Feb 26 '13 at 0:29

A factory reset will also fix this problem but be sure to back up your files when prompted to.

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Thanks Travis. I guess this is obvious to you, but I wonder how someone might initiate a factory reset while the laptop won't boot and you don't have access to a bootable USB or CD? –  Levi Dec 12 '13 at 21:34

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