Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Level 1

4 points

0x0000034 BCD Error Bootcamp, No Startup Repair

Hi! I have a late 2013 15" Macbook Pro which has been dual booted with OS X 10.11.3 and Windows 10.

After a particularly large set of Windows updates, upon restart I get an error stating that there are missing boot files (error 0x0000034). I have followed other threads and created a Windows 10 install media on an SD card, and am attempting to run Startup Repair to fix the BCD error.

However, when booting from the SD EFI icon in bootcamp, I get a message stating that it looks like I have begun an upgrade to Windows, would I like to continue the upgrade by removing the installation media, or instead perform a clean installation of Windows 10. If I remove the media, I get returned to the original blue error screen. If I attempt a clean install, I go through a few windows asking for language, input etc and then arrive at a window which asks where I want to install Windows 10.

There are 5 possible partitions available in the dialog window, and a variety of options including "Refresh" and "Format", but there is no option to run Startup Repair.

There is another icon/option that appears in bootcamp which is simply labeled "Windows". Attempting to boot from that icon gives the same results as booting from the EFI icon, but at a much lower screen resolution (everything is bigger and more jagged).

TL;DR: How do I run Startup Repair off of a bootable SD card, when Windows believes I was in the middle of an upgrade when the BCD files were lost?

Thanks in advance for the help!

Tech Specs:
Late 2013 15" Macbook Pro

OS X 10.11.3, Windows 10

2.3 GHz i7

16 GB 1600 MHz DDR3

NVIDIA GeForce GT 750M 2048 MB

500 GB Flash storage (334 GB on OS X, 164.6 GB on bootcamp partition)

MacBook Pro with Retina display, OS X El Capitan (10.11.3)

Posted on Apr 13, 2016 10:12 PM

80 replies

DietDrPhil Author

Level 1

4 points

Apr 15, 2016 5:17 PM in response to Loner T

I cant post a picture of it right now, but if I *don't* assign a letter to EFI, bcdedit returns the same device for Manager as in your picture.

Each time I restart the computer, I have to reassign the disk.

Loner T

Level 9

59,477 points

Apr 15, 2016 6:09 PM in response to DietDrPhil

Use the remove command in diskpart to remove the letter Q: and try to boot Windows normally.

DietDrPhil Author

Level 1

4 points

Apr 15, 2016 6:27 PM in response to Loner T

No luck. What do you think my options are at this point? How far do you think we are from figuring out a boot solution?

If I can't get it by tonight, I will probably attempt a reset. If I try a reset from the Troubleshooting GUI, will it just work wrt to Bootcamp, or will I need to take additional steps to get Windows to reset correctly with Bootcamp?

Loner T

Level 9

59,477 points

Apr 15, 2016 7:47 PM in response to DietDrPhil

Reset your PC should remove recent updates, but it relies on Windows System Restore point to rollback. Try it using the W10 installer. You may still see BCD issues.

DietDrPhil Author

Level 1

4 points

Apr 15, 2016 8:35 PM in response to Loner T

I attempted to rollback already just to see if it would work, and was told here weren't any restore points.

Is there a way for me to make a backup while in safe mode? Or will I have to manually grab all my files to back them up?

Loner T

Level 9

59,477 points

Apr 15, 2016 8:59 PM in response to DietDrPhil

If you are in safe mode, you have access to C:. Connect a large enough external disk to the second USB port, and copy non-Windows files to this external disk, after you verify it's drive letter. Once you have your files, you can remove W10, and re-install W10, and then restore your files. If you have applications, you will need to re-install them again.

DietDrPhil Author

Level 1

4 points

Apr 15, 2016 9:40 PM in response to Loner T

By verify, what do you mean?

Loner T

Level 9

59,477 points

Apr 15, 2016 9:46 PM in response to DietDrPhil

Ensure that the drive letter assigned to the external disk does not conflict with your EFI partition. You do not want to overwrite the EFI inadvertently, because it will cause OS X problems too.

Loner T

Level 9

59,477 points

Apr 16, 2016 7:29 AM in response to DietDrPhil

Was the read-only attribute cleared on C: when BCD was rebuilt on the EFI partition, in any of your attempts? See the attribute command in https://technet.microsoft.com/en-us/library/cc766465(v=ws.10).aspx .