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Windows Will Not Boot

I have tried several things I have seen on other discussions, from many different websites, and I still cant get Windows working again.

Whenever I think I am close to fixing it, it says "Missing operating system". I have done startup repair, but it won't work.

It started when I tried to resize my OS X partition if it helps. I noticed a guy named 'Loner T' seemed pretty good at this, if he is available I would like his help.

iMac (21.5-inch Mid 2011), OS X Yosemite (10.10.3)

Posted on Jun 22, 2015 1:20 AM

Reply
39 replies

Jun 23, 2015 8:47 AM in response to Loner T

Ok.

8:

Can't open filesystem. Filesystem seems damaged.

11:

Support for this filesystem hasn't been implemented.

12:

http://pastebin.com/UPyTwdLU

I feel so ******* ******** right now. I pressed enter instead of 'P' at 13.

Anyways, 12 looks to be my file system. May I ask why this is necessary? On other threads I never saw this being used. I just wan't my Windows partition to be bootable again. I would much prefer I don't use that tool any more, i'm way to clumsy for it.

Jun 23, 2015 9:10 AM in response to HF.2552202

Entry 12 looks very reasonable. Here is a table to verify the disk addresses.


GPT 3 StartGPT 3 SizeGPT 3 EndNTFS StartSector OffsetNTFS SizeNTFS EndSector Offset (MB)NTFS(Gb)
135948784126953613721832029464985615743153668212325797677311276,871325.2617154


Does the size of the Windows partition look reasonable. Please also notice there is about 76GB disk space which will be lost between GPT3 and new GPT4.


The reason each partition is scanned is to verify the contents, ensure the file system is intact and viable as a partition. Here is an example - I can't boot into my windows after resizing my partition .

Jun 23, 2015 10:05 AM in response to HF.2552202

Let us assume this is the correct partition.


Install GPT Fdisk (aka gdisk).

Leave your Testdisk display and start a new Terminal Window. You need to use the following steps. If you see any error messages during the following steps, please stop and post back here with the error message. The following steps have values from your Testdisk output (and you can verify) in Steps 7 and 8. Please notice the '+' sign in step 8 (this is called offset notation). The text in parentheses is for informational purpose to describe the action being taken. Gdisk has one-character commands except when entering numbers.


Rebuild GPT4 using start/end offsets


  1. Sudo gdisk /dev/rdisk0
  2. P (print the full list of parts)
  3. D (delete)
  4. 4 (part 4)
  5. N (new part)
  6. 4 (part 4)
  7. 294649856 ( - Start offset in bytes or the start point for Bootcamp part)
  8. +682123257 ( - Size offset, as opposed to End offset)
  9. 0700 (Windows part type)
  10. P (print list of all parts just to see what changes will be made)
  11. W (Write the new GPT)
  12. Y (Yes! really write the new GPT)

This will delete and re-write the GPT partition info for /dev/disk0s4.

Rebuild MBR to match the new GPT information thus resetting the Hybrid MBR. Use defaults for other questions (like partition codes). The only values that need modifications are the Boot flags and step 10. Accept all other defaults that Gdisk offers. Please see thesample Q&A as an example. These steps can be repeated if you make a mistake before you get to Step 12, otherwise start from Step 1 for these steps. Step 6 has numbers which are typed with a space between the numbers. If you get a message about additional space found, press 'n' and continue.

  1. Sudo gdisk /dev/rdisk0
  2. P (Print list of parts)
  3. R (Recover)
  4. O (print current Hybrid MBR)
  5. H (chooses Hybrid)
  6. Partitions numbers to be hybridized: 2 3 4
  7. Y (Good for GRUB question)
  8. N (part 2 boot flag)
  9. N (part 3 boot flag)
  10. Y (part 4 boot flag make NTFS bootable partition)
  11. O (print current Hybrid MBR)
  12. W (Write the new MBR)
  13. Y (Yes! write the new MBR)
  14. Reboot


Here is sample Q&A for this section. Please notice the Press Enter/Return.


Place EFI GPT (0xEE) partition first in MBR (good for GRUB)? (Y/N): Y


Creating entry for GPT partition #2 (MBR partition #2)

Enter an MBR hex code (default AF): Press Enter/Return

Set the bootable flag? (Y/N): N


Creating entry for GPT partition #3 (MBR partition #3)

Enter an MBR hex code (default AB): Press Enter/Return

Set the bootable flag? (Y/N): N


Creating entry for GPT partition #4 (MBR partition #4)

Enter an MBR hex code (default 07): Press Enter/Return

Set the bootable flag? (Y/N): Y


Test 1 - Does Bootcamp Volume show up in Finder?

Test 2 - Can you see files in Bootcamp Volume?

Test 3 - Can you select Bootcamp in System Preferences -> Startup Disk?

Test 4 - If Test 3 is successful, select Bootcamp and Click Restart.

Windows Will Not Boot

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