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Messed Up Bootcamp Partition

Hello

Thanks to anyone who reads this or can provide any help.

System

iMac (27-inch, Late 2009)

iMac 10, 1

El Capitan 10.11.1

Windows 10 via bootcamp. Started as Windows 7 HP and upgraded via Windows 8 pro and 8.1 pro.

Background

About 2 weeks ago I started having problems with my computer and could not get OSX to boot. I don't know what I did but only Windows would start. I was also able to get into the recovery partition. I was able to see the os x partition from within windows. It just would not boot. The Apple icon came up on screen and th progress bar got about 3/4's of the way across the screen then the iMac shutdown.

I tried a number of solutions from different websites but could not get beyond this.

I decided what I was going to do was back up my computer and reinstall. I new I had a Time Machine back up of OS X to within a few days but I didn't want to lose my windows partition so I bought a external hard disk and got a cheap copy of Acronis True Image included as a special offer. I installed this on the Windows partition I backed up a complete image of Windows and OS X partitions. I used the software to create a Acronis bootable recovery usb.

I Then used Disk Utility from my original Snow Leopard install disk's to wipe the disk back to a Single HFS+ Partition. I Installed Snow Leopard and then all updates to get my computer back to El Capitan. So far so good and all working. I then used the migration assistant with my Time Machine back up and got all my Apps files and settings back. So at this point OS X was going fine.

To get windows back I then used Disk Utility to partition half my 1 TB as FAT32 with the intent of using the recovery USB to recover the Windows partition. However I found the USB would not boot. I discovered later that disabling system integrity from the Recovery Partition then seems to let the USB key boot but I only found this out by accident later when I had left the key in and I rebooted after disabling the above.

So being stuck without a way to recover my backed up partition I had the bright idea! to use Disk Utility to partition a separate 100GB from my mac partition to another FAT32 partition. I then installed my original Windows 7 to this 100GB partition. I then reinstalled my Acronis True Image software to this and then used this to recover the Windows image to the 500GB partition that I originally created.

The recovery process seemed to go well and once completed I was able to view the partition in os x but I could not boot in to it. After a little further research I discovered the 4 partition limit on GPT and realised I now had managed to created 5. The EFI, OS X, OS X recovery, 100GB Windows 7 and the 500GB recovered Partition.

So my next idea was that now that I had my original windows recovered and I could view the files I thought I could Use Disk Utility Again to Delete the 100GB partition and resize the OS X partition back up to 500GB Also. I have done this and I followed the guide here http://www.rodsbooks.com/refind/installing.html#sluggish to fix Windows boot problems as I thought that may help.

This didn't work but I also read about Hybrid partition tables and how if these got problems that Windows may not boot. I then came across this forum and noticed that there may be a solution to recover/fix the partition tables.

Screen Prints

I have taken some screen prints of the commands and outputs that I have seen recommended in this forum. I would hope with these someone can point me in the correct direction.

I Searched using the EFI GPT option in test disk.

I Added Screen prints below of what you get from selecting p:list files with each of the non mac partitions listed above.

Thanks for looking and I hope someone can post me in the correct direction. If you need any other screen prints please let me know.

Regards.

iMac (27-inch Late 2009), OS X El Capitan (10.11.1)

Posted on Nov 28, 2015 4:41 PM

Best reply

Loner T

Level 9

59,471 points

Posted on Dec 6, 2015 5:35 PM

On this screen - Screen+Shot+2015-11-26+at+01.08.58.png you have the Testdisk reported start/end/size values. The values are the same as second MS Data entry on Screen+Shot+2015-11-26+at+01.07.02.png . This is also the last entry in your MBR.

In your MBR, you have a boot flag missing. Disable SIP (System Integrity Protection) and run the following commands in OSX Terminal and test. Please ignore i386 MBR message, but not any other messages, in the following steps.

sudo fdisk -e /dev/disk0

flag 4

Reboot and test.

View in context

21 replies

Dec 1, 2015 3:06 PM in response to quantum-spinecho

And this is the EFI listing:

FrancisownsiMac:~ francis$ sudo mkdir -p /volumes/efi

Password:

FrancisownsiMac:~ francis$ sudo mount -t msdos /dev/disk0s1 /volumes/efi

FrancisownsiMac:~ francis$ ls -lR /Volumes/EFI

total 1

drwxrwxrwx 1 francis staff 512 15 Nov 11:45 EFI

/Volumes/EFI/EFI:

total 3

drwxrwxrwx 1 francis staff 512 15 Nov 11:45 APPLE

drwxrwxrwx 1 francis staff 512 1 Jan 1970 Boot

drwxrwxrwx 1 francis staff 512 1 Jan 1970 Microsoft

/Volumes/EFI/EFI/APPLE:

total 1

drwxrwxrwx 1 francis staff 512 15 Nov 11:45 EXTENSIONS

/Volumes/EFI/EFI/APPLE/EXTENSIONS:

total 30722

-rwxrwxrwx 1 francis staff 15729264 1 Dec 22:47 Firmware.scap

/Volumes/EFI/EFI/Boot:

/Volumes/EFI/EFI/Microsoft:

total 6

drwxrwxrwx 1 francis staff 3072 1 Jan 1970 Boot

/Volumes/EFI/EFI/Microsoft/Boot:

total 6551

drwxrwxrwx 1 francis staff 512 1 Jan 1970 bg-BG

-rwxrwxrwx 1 francis staff 4391 1 Oct 02:59 boot.stl

-rwxrwxrwx 1 francis staff 1155424 1 Oct 05:59 bootmgfw.efi

-rwxrwxrwx 1 francis staff 1151840 1 Oct 05:59 bootmgr.efi

drwxrwxrwx 1 francis staff 512 1 Jan 1970 cs-CZ

drwxrwxrwx 1 francis staff 512 1 Jan 1970 da-DK

drwxrwxrwx 1 francis staff 512 1 Jan 1970 de-DE

drwxrwxrwx 1 francis staff 512 1 Jan 1970 el-GR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 en-GB

drwxrwxrwx 1 francis staff 512 1 Jan 1970 en-US

drwxrwxrwx 1 francis staff 512 1 Jan 1970 es-ES

drwxrwxrwx 1 francis staff 512 1 Jan 1970 es-MX

drwxrwxrwx 1 francis staff 512 1 Jan 1970 et-EE

drwxrwxrwx 1 francis staff 512 1 Jan 1970 fi-FI

drwxrwxrwx 1 francis staff 512 1 Jan 1970 fr-CA

drwxrwxrwx 1 francis staff 512 1 Jan 1970 fr-FR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 hr-HR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 hu-HU

drwxrwxrwx 1 francis staff 512 1 Jan 1970 it-IT

drwxrwxrwx 1 francis staff 512 1 Jan 1970 ja-JP

drwxrwxrwx 1 francis staff 512 1 Jan 1970 ko-KR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 lt-LT

drwxrwxrwx 1 francis staff 512 1 Jan 1970 lv-LV

-rwxrwxrwx 1 francis staff 1022304 25 Sep 06:01 memtest.efi

drwxrwxrwx 1 francis staff 512 1 Jan 1970 nb-NO

drwxrwxrwx 1 francis staff 512 1 Jan 1970 nl-NL

drwxrwxrwx 1 francis staff 512 1 Jan 1970 pl-PL

drwxrwxrwx 1 francis staff 512 1 Jan 1970 pt-BR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 pt-PT

drwxrwxrwx 1 francis staff 512 1 Jan 1970 qps-ploc

drwxrwxrwx 1 francis staff 512 1 Jan 1970 ro-RO

drwxrwxrwx 1 francis staff 512 1 Jan 1970 ru-RU

drwxrwxrwx 1 francis staff 512 1 Jan 1970 sk-SK

drwxrwxrwx 1 francis staff 512 1 Jan 1970 sl-SI

drwxrwxrwx 1 francis staff 512 1 Jan 1970 sr-Latn-CS

drwxrwxrwx 1 francis staff 512 1 Jan 1970 sr-Latn-RS

drwxrwxrwx 1 francis staff 512 1 Jan 1970 sv-SE

drwxrwxrwx 1 francis staff 512 1 Jan 1970 tr-TR

drwxrwxrwx 1 francis staff 512 1 Jan 1970 uk-UA

drwxrwxrwx 1 francis staff 512 1 Jan 1970 zh-CN

drwxrwxrwx 1 francis staff 512 1 Jan 1970 zh-HK

drwxrwxrwx 1 francis staff 512 1 Jan 1970 zh-TW

/Volumes/EFI/EFI/Microsoft/Boot/bg-BG:

total 304

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/cs-CZ:

total 389

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/da-DK:

total 387

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/de-DE:

total 400

-rwxrwxrwx 1 francis staff 79200 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 79200 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/el-GR:

total 404

-rwxrwxrwx 1 francis staff 79712 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 80224 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 46432 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/en-GB:

total 290

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/en-US:

total 378

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 44896 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/es-ES:

total 394

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/es-MX:

total 303

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/et-EE:

total 294

-rwxrwxrwx 1 francis staff 75104 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 75104 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/fi-FI:

total 389

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/fr-CA:

total 309

-rwxrwxrwx 1 francis staff 78688 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 79200 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/fr-FR:

total 400

-rwxrwxrwx 1 francis staff 79200 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 79200 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/hr-HR:

total 300

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/hu-HU:

total 398

-rwxrwxrwx 1 francis staff 78688 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 78688 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/it-IT:

total 391

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/ja-JP:

total 349

-rwxrwxrwx 1 francis staff 67936 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 67424 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 42848 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/ko-KR:

total 347

-rwxrwxrwx 1 francis staff 67424 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 66912 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 42848 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/lt-LT:

total 296

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/lv-LV:

total 296

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/nb-NO:

total 385

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 75616 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/nl-NL:

total 394

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 78176 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/pl-PL:

total 394

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77664 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/pt-BR:

total 389

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/pt-PT:

total 390

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45920 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/qps-ploc:

total 379

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 74080 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/ro-RO:

total 298

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/ru-RU:

total 389

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 44896 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/sk-SK:

total 302

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/sl-SI:

total 300

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76640 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/sr-Latn-CS:

total 391

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/sr-Latn-RS:

total 302

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/sv-SE:

total 386

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 76128 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 44896 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/tr-TR:

total 383

-rwxrwxrwx 1 francis staff 75104 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 75104 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 45408 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/uk-UA:

total 302

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 77152 10 Jul 13:00 bootmgr.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/zh-CN:

total 333

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 42336 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/zh-HK:

total 333

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 42336 10 Jul 13:00 memtest.efi.mui

/Volumes/EFI/EFI/Microsoft/Boot/zh-TW:

total 333

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgfw.efi.mui

-rwxrwxrwx 1 francis staff 63840 10 Jul 13:00 bootmgr.efi.mui

-rwxrwxrwx 1 francis staff 42336 10 Jul 13:00 memtest.efi.mui

FrancisownsiMac:~ francis$

Loner T

Level 9

59,471 points

Dec 1, 2015 3:14 PM in response to quantum-spinecho

1. Check if CBS.LOG exists.

2. If you notice, some of the files that you need to boot are missing from the EFI directory. For example...

/Volumes/EFI/EFI/Microsoft/Boot:

total 8731

-rwxrwxrwx 1 staff 45056 26 Aug 23:05 BCD

-rwxrwxrwx 1 staff 40960 26 Aug 15:35 BCD.LOG

-rwxrwxrwx 1 staff 0 26 Aug 15:39 BCD.LOG1

-rwxrwxrwx 1 staff 0 26 Aug 15:39 BCD.LOG2

-rwxrwxrwx 1 staff 65536 26 Aug 21:07 BOOTSTAT.DAT

drwxrwxrwx 1 staff 1536 26 Aug 15:39 Fonts

drwxrwxrwx 1 staff 512 26 Aug 15:39 Resources

drwxrwxrwx 1 staff 512 26 Aug 15:39 bg-BG

-rwxrwxrwx 1 staff 4247 10 Jul 12:30 boot.stl

3. Please notice the dates. You have dates of 1 Jan 1970 (Unix time = 0) while the linked thread has valid dates.

Dec 1, 2015 4:13 PM in response to Loner T

1. CBS.LOG last saved on 14th November. I think the screen said it does not save in offline scenarios.

2. I have had a look and can see there is good deal of difference in the file lists.

3. I see that also.

Can we rebuild by following instructions like: http://woshub.com/how-to-repair-uefi-bootloader-in-windows-8/ or something similar.

Thanks again for answering my questions. I am finding this very informative also.

Loner T

Level 9

59,471 points

Dec 1, 2015 6:28 PM in response to quantum-spinecho

Yes, you can try that link. My suggestion is run a DD command and get the EFI partition copied, or mount and make an image using Disk Utility. Once you have it saved, then try that article.

A OSX backup would also be a good additional safety step.

Dec 6, 2015 5:44 PM in response to Loner T

Hello

Just wanted to come back and thank Loner T for all help provided.

I will mark the post where you helped me sort making the partition bootable as the solution as I think that was the main break through to the original problem.

Some commentary on where I got to:

My last idea didn't work but I came accross a solution that is useable but not ideal.

I followed the guide here http://jmeosbn.github.io/blog/windows-8.1-efi-install/ and got Windows 10 installed and working.

I had tried and failed at first to install with just the windows 10 installer as it wanted to create about 4 partitions in the empty space and this included a second EFI partition.

I had to use gdisk to remove all the extra partitions and then followed the guide above.

I had to make sure I didn't use disk utility to create a FAT32 area as that installed the Hybrid MBR and then that stops the Windows 10 Installer when it comes to selecting a disk partition to install to.

I also got the same black screen error that I had when I originally installed Windows 7 with ATI graphics driver so had to reboot to the command line and delete the offending file.

I tried loading the legacy drivers for the 4850 from the AMD ATI site but I just got a black screen after reboot so I think I am stuck with the generic Microsoft driver. I did read somewhere that there is a windows 10 driver but that it was only released through windows update. Will have to look more into that later. I thought I had a proper driver installed when I originally upgraded from 8.1 to 10 so I don't understand why they won't install now.

I'm also of the opinion now that the reason we couldn't get my original partition to boot that I had copied back in from the acronis image is that the windows 10 software on the usb key just like the installer was probably looking for the installation to be EFI/GPT in the same way as the installer so the commands that could be issued through the command line to try and rebuild the boot structures were probably never going to set things up correctly given my windows 10 install had been originally installed as upgrade upon upgrade from windows 7.As such this had the legacy hang over of the bootcamp hybrid mbr emulated bios boot method.

Thanks again Loner T for all your help. I fell I am a lot more educated now in these things and that is no small part to your good guidance you have provided to me and many others on these forums. It got me into reading a good deal more about this stuff.

Edit: Also meant to say will now be able to get my files back from the Acronis backup but will have reinstall software I want. Good reason to keep things tidy.

I will continue to keep Time Machine Running. I was very impressed by how easy it was to get all my software, settings and files back through the migration assistant to the clean install I made from the USB key. I will also set up Acronis to keep an incremental back up for windows. May not be as easy to reinstall everything but at least I will now all files are safe.

Loner T

Level 9

59,471 points

Dec 6, 2015 5:41 PM in response to quantum-spinecho

Please ensure you have good backups.

Messed Up Bootcamp Partition