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Loner T Author

Level 9

59,513 points

Bootcamp and Yosemite upgrade - potential data loss warning

There are two specific cases that I am currently aware of which indicate potential data loss during Yosemite upgrade.

Please see

"Missing Operating system_ " After installing Yosemite

Windows 7 partition gone after installing Yosemite

This is the other side affect of Yosemite upgrade, which is lost functionality

windows 8 does not recognise Macintosh HD, No drive Letter

Please avoid an upgrade to Yosemite if you also have Bootcamp, till the data loss issue has been investigated and root cause established.

Posted on Oct 17, 2014 9:56 PM

55 replies

Loner T Author

Level 9

59,513 points

Nov 30, 2014 7:36 PM in response to drizzy19

This points to my Data loss thread. 😉 You may have a different link for your thread.

drizzy19

Level 1

0 points

Nov 30, 2014 10:03 PM in response to Loner T

Bah, yep. Apologies, though it seems you already found it anyway. 🙂

Can't install Windows using Bootcamp after Yosemite Upgrade

tdho

Level 1

0 points

Jan 5, 2015 11:23 AM in response to Loner T

Hi Loner T. I'm new to this topic, but I've read lots of problems regarding hybrid MBR bootcamp.

I heard that EFI bootcamp won't cause that much problem, and apple began to support EFI on their products since 2013 generation.

I got macbook pro 15" mid 2012 (MD103), I did a little research on google, and I found this -> EFI and SMC firmware updates for Intel-based Macs - Apple Support

If I update the firmware, does it make my MBP got EFI bootcamp?

I've read your instruction to upgrade OS X on hybrid MBR using winclone, but I thought it would be nice if I could get my MBP to work on EFI.

I post my question here, so I hope that you would help me. Since you are good at this topic.

I might create a new thread after this. Sorry for my english.

Loner T Author

Level 9

59,513 points

Jan 5, 2015 7:10 PM in response to tdho

tdho wrote:

I got macbook pro 15" mid 2012 (MD103), I did a little research on google, and I found this -> EFI and SMC firmware updates for Intel-based Macs - Apple Support

If I update the firmware, does it make my MBP got EFI bootcamp?

From How to identify MacBook Pro models - Apple Support your MBP is MacBookPro9,1, which is considered a preUEFI model in the BC Info.plist. I am not aware of Apple retrofitting Macs for UEFI support.

<key>PreUEFIModels</key>

<array>

<string>MacBook7</string>

<string>MacBookAir5</string>

<string>MacBookPro10</string>

<string>MacPro5</string>

<string>Macmini6</string>

<string>iMac13</string>

</array>

Despite this, I have tried EFI on a 13" 2012 MBP with Windows 8.1 and have had limited success in a full EFI boot.

I've read your instruction to upgrade OS X on hybrid MBR using winclone, but I thought it would be nice if I could get my MBP to work on EFI.

You should still try an EFI boot and see if newer drivers may be able to help, if possible and the Mac you have may be unavailable for a day or two. Please ensure you have backups of OSX and Windows, before you make any changes.

mrgazz

Level 1

0 points

Feb 10, 2015 9:51 AM in response to Loner T

Hi Loner T,

I created a new thread here with my problem. Thank you in advance for all the help you have given everyone! - Mike

Repairing boot camp after OS install 10.10.2

Mar 17, 2015 1:07 PM in response to mrgazz

Would it make sense to backup all the data in your Windows OS, "undo" the partition and go back to how you had your computer before installing Windows using Bootcamp. Then install the update to Yosemite, and redo the whole process of installing Windows using Bootcamp in the new Yosemite OS?

I haven't tried it, does this sound reasonable?

Jul 28, 2015 4:23 AM in response to Loner T

I didn't know that the devs could be such morons!

I suppose I should make a fresh install of windows after the upgrade 😐

tnx Loner

Loner T Author

Level 9

59,513 points

Jul 28, 2015 4:25 AM in response to A-L-P-H-A

Can you post a new discussion and include the output of the following Terminal commands? It may be possible to salvage the current installation.

diskutil list

diskutil cs list

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

The "sudo" commands will prompt for your password, and it will not be echoed back. You may also see a warning about improper use of "sudo" and potential data loss due to "abuse" of the command.

Oct 19, 2015 3:42 AM in response to Loner T

Hi Loner, I am trying to fix my bootcamp but I cannot follow these forums. Could you please help?

Last login: Mon Oct 19 20:40:26 on ttys000

Shauns-MacBook-Pro:~ shaunward$ diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *500.1 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage Macintosh HD 300.0 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 20.0 GB disk0s4

/dev/disk1 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +299.6 GB disk1

Logical Volume on disk0s2

06982F89-8A63-494B-94FD-414D3FB68815

Unencrypted

Shauns-MacBook-Pro:~ shaunward$ diskutil cs list

CoreStorage logical volume groups (1 found)

+-- Logical Volume Group EABF9C2F-6780-4FEA-96BB-3BB71720340E

=========================================================

Name: Macintosh HD

Status: Online

Size: 299999997952 B (300.0 GB)

Free Space: 18919424 B (18.9 MB)

+-< Physical Volume 4F2BB37D-8F1F-4E4C-8D6B-A7427648EF51

| ----------------------------------------------------

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 299999997952 B (300.0 GB)

+-> Logical Volume Family 119E1CA6-3759-4C7E-A799-261E70EA183A

----------------------------------------------------------

Encryption Type: AES-XTS

Encryption Status: Unlocked

Conversion Status: Converting (backward)

Reversion State: Decrypting

High Level Queries: Not Fully Secure

| Has Visible Users

| Has Volume Key

+-> Logical Volume 06982F89-8A63-494B-94FD-414D3FB68815

---------------------------------------------------

Disk: disk1

Status: Online

Size (Total): 299628756992 B (299.6 GB)

Conversion Progress: 32%

Revertible: Yes (unlock and decryption required)

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS

Shauns-MacBook-Pro:~ shaunward$ sudo gpt -vv -r show /dev/disk0

gpt show: /dev/disk0: mediasize=500107862016; sectorsize=512; blocks=976773168

gpt show: /dev/disk0: Suspicious MBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 976773167

start size index contents

0 1 MBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 585937496 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

586347136 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

587616672 350094944

937711616 39061504 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

976773120 15

976773135 32 Sec GPT table

976773167 1 Sec GPT header

Shauns-MacBook-Pro:~ shaunward$ sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 60801/255/63 [976773168 sectors]

Signature: 0xAA55

Starting Ending

#: id cyl hd sec - cyl hd sec [ start - size]

------------------------------------------------------------------------

1: EE 1023 254 63 - 1023 254 63 [ 1 - 409639] <Unknown ID>

2: AC 1023 254 63 - 1023 254 63 [ 409640 - 585937496] <Unknown ID>

3: AB 1023 254 63 - 1023 254 63 [ 586347136 - 1269536] Darwin Boot

4: 0C 1023 254 63 - 1023 254 63 [ 937711616 - 39061504] Win95 FAT32L

Shauns-MacBook-Pro:~ shaunward$

Loner T Author

Level 9

59,513 points

Oct 19, 2015 4:35 AM in response to shaunfromkybong

Can you start a new discussion (Find answers and ask new questions ) and post this information on the new thread to avoid confusion?

Bootcamp and Yosemite upgrade - potential data loss warning