el capitan's boot camp assistant unable to install windows 10

Question

el capitan's boot camp assistant unable to install windows 10

My config : a new macbook air 11" (MacBook Air 7,2) preloaded with OS X Yosemite (10.9.x), soon updated to El Capitan "GM" then El Capitan (15A284).

Problem : unable to install Windows 10 due to numerous bugs and problems.

The new "Boot Camp Assistant" of OS X El Capitan offer to prepare a somewhat nice temporary Windows 10 installation partitions (OSX RESERVED?) to streamline the windows 10 installation. But it doesn't work! When Windows 10 installer starts it claims "a missing driver is needed to continue", driver that is nowhere to be found. (as I read elsewhere on the net, it happens that the SSD driver found in the last Bootcamp ESD is at fault).

The problem is :

- I can't install WIN10 as is recommended by Apple

- I can't easily or "legitimately" alter the "OS X RESERVED" partition before windows 10 installation (the time is short between end of download and reboot).

- This "OS X RESERVED" partition is erased automatically (which were nice if win10 install had worked) AND "BootCamp Assistant" restart all the process each time (ssd partition - win10 iso lookup and file copy - download drivers…) - It take roughly 30min each time (this download is oddly sssloooow).

AND - I can't create a USB drive which would work for sure!

(PS - Since I downloaded 2 times the Win10 iso directly from Microsoft, I haven't a single doubt of this file integrity).

My question : who else encounter this problem? And is there a known solution?

MacBook Air, OS X El Capitan (10.11)

Posted on Oct 3, 2015 9:29 AM

Reply

Answer 1

Loner T

Level 9

59,471 points

Oct 3, 2015 11:43 AM in response to Renaud DERRIEN

Renaud DERRIEN wrote:

The new "Boot Camp Assistant" of OS X El Capitan offer to prepare a somewhat nice temporary Windows 10 installation partitions (OSX RESERVED?) to streamline the windows 10 installation. But it doesn't work! When Windows 10 installer starts it claims "a missing driver is needed to continue", driver that is nowhere to be found. (as I read elsewhere on the net, it happens that the SSD driver found in the last Bootcamp ESD is at fault).

This is an issue with the ISO used to build the USB Installer. The downloaded ISO has been corrupted during the download. The AppleSSD64 is not your first issue. AppleSSD.sys comes into play after Windows is installed, not during installation. Please see [urgent]get "appleSSD.sys" error when installing windows 7 through bootcamp for details.

The problem is :

- I can't install WIN10 as is recommended by Apple

- I can't easily or "legitimately" alter the "OS X RESERVED" partition before windows 10 installation (the time is short between end of download and reboot).

- This "OS X RESERVED" partition is erased automatically (which were nice if win10 install had worked) AND "BootCamp Assistant" restart all the process each time (ssd partition - win10 iso lookup and file copy - download drivers…) - It take roughly 30min each time (this download is oddly sssloooow).

OS X Reserved is a temporary hold area. It is meant to be deleted after the installer is successfully built.

(PS - Since I downloaded 2 times the Win10 iso directly from Microsoft, I haven't a single doubt of this file integrity).

My question : who else encounter this problem? And is there a known solution?

Please verify the MD5sum or SHA1 of the downloaded ISO on your Mac with the source where you downloaded it from. The missing CD/DVD driver is because there is block corruption in the ISO and the Microsoft downloader does not verify the checksums between the source and the downloaded destination.

Reply

Answer 2

Oct 3, 2015 2:42 PM in response to Renaud DERRIEN

For the user who replied (and later pulled his/her reply) :

It cannot be a windows10 download error since the SHA1 of the file match! (Okay for this release it is rather hard to find official SHA1 number but if I suffered from download errors it would be surprising to find the same SHA hash for other users...

As a matter of fact I happened to chat with Apple Support.

lesson 1 : apparently "Bootcamp assistant" should make an USB Thumbdrive (or the fact that apple let install windows 10 without it is not known everywhere).

lesson 2 : it could be a problem with CoreStorage.

And I read somewhere It could be a problem with the way the SSD drive is connected to the mainboard : for TWO models (macbook12" and macbookair11") apple discarded classic SATA for a more modern nvme (non volatile memory express), a flavor of PCI-Express.

Somewhere in the process windows "forget" where it has stored the boot drive (which contains installation files and drivers) - probably because windows install mount a some point boot.wim as a base for windows installation (in the process it somehow forget where this boot.wim came from...

Reply

Answer 3

Loner T

Level 9

59,471 points

Oct 3, 2015 4:18 PM in response to Renaud DERRIEN

Renaud DERRIEN wrote:

For the user who replied (and later pulled his/her reply) :

It cannot be a windows10 download error since the SHA1 of the file match! (Okay for this release it is rather hard to find official SHA1 number but if I suffered from download errors it would be surprising to find the same SHA hash for other users...

Can you post which edition of W10 you downloaded and its MD5 and SHA1? I can download the same and verify if we get the same download. Why is Microsoft not willing to publish MD5/SHA1 on the software download website is rather bizarre .

lesson 1 : apparently "Bootcamp assistant" should make an USB Thumbdrive (or the fact that apple let install windows 10 without it is not known everywhere).

From Use Windows 10 on your Mac with Boot Camp - Apple Support, The following is an in-place upgrade set of instructions (steps 4-7).

Upgrading from 64-bit versions of Windows

You can upgrade existing 64-bit installations of Windows 7, or 8.1 to Windows 10. You need at least 10 GB of free space on your Windows partition. If you have Windows 8.0, update to Windows 8.1 before upgrading to Windows 10.

Use the list at the end of this article to make sure you have a Mac that supports Windows 10.

Start your Mac from OS X.

When your Mac desktop appears, choose App Store from the Apple menu. Click the Updates tab in the App Store window to check for software updates. Make sure OS X and your Mac firmware are up to date.

Start your Mac from the version of Windows you currently have installed.

Open Apple Software Update for Windows and install available updates, including the FaceTime Camera Update.

Use the Windows installer to upgrade Windows.

After installation is complete, open Apple Software Update for Windows again and install available updates to make sure the Windows Support Software (drivers) for Boot Camp are up to date. As part of driver installation, your Mac might restart one or more times.

After driver installation is complete, log in to Windows to begin using Windows 10 on your Mac.

lesson 2 : it could be a problem with CoreStorage.

No. Please see Re: Windows 10 upgrade fail 80073B92-20009 Fusion Drive iMac .

And I read somewhere It could be a problem with the way the SSD drive is connected to the mainboard : for TWO models (macbook12" and macbookair11") apple discarded classic SATA for a more modern nvme (non volatile memory express), a flavor of PCI-Express.

Somewhere in the process windows "forget" where it has stored the boot drive (which contains installation files and drivers) - probably because windows install mount a some point boot.wim as a base for windows installation (in the process it somehow forget where this boot.wim came from...

Is this not a Windows Installer issue?

Reply

Answer 4

Oct 4, 2015 6:58 AM in response to Renaud DERRIEN

I am having the same problem. and still not able to solve this problem up till now. I am having the same error "media driver missing" when I was trying to install windows 10 on my Macbook Air 11" 2015

Is there anyway that I can install windows from a USB Driver with windows 10 installer?

Reply

Answer 5

Oct 4, 2015 8:21 AM in response to Steve Chun

Okay I did found a sort-off workaround.

Since I double checked the windows 10 iso (with MD5 and SHA1 hash I found on a webpage elsewhere because Microsoft didn't found useful to publish it), I'm sure the problem doesn't come from the windows installer alone.

On my system I "reverted" my HDD from the now standard "CoreStorage logical partition format" to the legacy plain GPT one. From what I've read and understand, the problem could start from here. > The BootCamp Assistant create a temporary partition called OSXRESERVED on some newish macs (including MacBook Air 11" early 2015). The installation process could take for granted the HDD is an array of logical CoreStorage partitions...

The workaround :

- for testing purpose I "saved" all the files written on this OSXRESERVED temp partition to a FAT32 formatted partition on a USB3 HDD (also in plain GPT format - not MBR!!)

1 - To gain access to OSXRESERVED partition, when in finder do command-MAJ-G then type " /Volumes/OSXRESERVED "

2 - copy all files found to a prepared FAT32 partition (of min 8GB)

- in order to do it I had to kill BootCamp Assistant at the good time (when the windows iso is copied to OSXRESERVED drive and the drivers from WindowsSupport.dmg are also written to it). (the command I used is "command-MAJ-esc" then select force quit BCA)

- You can first download WindowsSupport.dmg with BCA (there is a function in the menu to do that) - then restart the BCA process normally… Then "force quit" a good step before the re-downloading the drivers (I did that in order to avoid the impromptu reboot).

3 - Ta-da : you have created the USB Drive you wanted (and which Apple should make an option to do anyway), albeit manually.

4 - This USB Windows Installation partition is NOT erased at each start - so you can manually change the drivers according your needs.

5 - In my case, this Partition worked flawlessly.

6 - You may have to erase the OSXRESERVED partition since it weren't used at all > using diskutil.

PS : I didn't use a purported USB flash thumbdrive, because it's rather slow to write on. (even with USB3).

PS2 : For a unknown reason I couldn't create this partition manually (copying Win.iso files and Bootcamp drivers manually) : the boot sequence didn't worked. It can be because a file/partition blessing I haven't wanted to find and learn about.

Reply

Answer 6

Loner T

Level 9

59,471 points

Oct 4, 2015 8:43 AM in response to Steve Chun

Steve Chun wrote:

I am having the same problem. and still not able to solve this problem up till now. I am having the same error "media driver missing" when I was trying to install windows 10 on my Macbook Air 11" 2015

Is there anyway that I can install windows from a USB Driver with windows 10 installer?

Your 2015 Mac is a UEFI-compliant Mac, and does not need BC Assistant. You can create a Free Space partition using Disk Utility and then directly use the Windows Installer to boot from using Apple Boot Manager (Alt/Option key at power up).

Reply

Answer 7

Loner T

Level 9

59,471 points

Oct 4, 2015 8:50 AM in response to Renaud DERRIEN

Renaud DERRIEN wrote:

2 - copy all files found to a prepared FAT32 partition (of min 8GB)

- in order to do it I had to kill BootCamp Assistant at the good time (when the windows iso is copied to OSXRESERVED drive and the drivers from WindowsSupport.dmg are also written to it). (the command I used is "command-MAJ-esc" then select force quit BCA)

- You can first download WindowsSupport.dmg with BCA (there is a function in the menu to do that) - then restart the BCA process normally… Then "force quit" a good step before the re-downloading the drivers (I did that in order to avoid the impromptu reboot).

This is the official method and is option 2 (Download Software) on BCA.

3 - Ta-da : you have created the USB Drive you wanted (and which Apple should make an option to do anyway), albeit manually.

If you enable the options for USB Installer and Download Software (1 and 2 respectively), you will create a USB Installer, which can be used multiple times and modified as necessary.

Reply

Answer 8

Oct 5, 2015 9:13 AM in response to Loner T

Thank you so much for your help. I have successfully installed the windows 10 by selecting the appropriate SSD driver in the Bootcamp "WindowsSupport" folder.

Reply

Answer 9

Oct 16, 2015 5:27 AM in response to Steve Chun

Hi. I can't to install windows 10 on my macbook air 11 inch early 2015 too.

The same problem with no media driver etc.

Please, tell how do you install windows 10 on you laptop using?

How to select the appropriate SSD driver in the Bootcamp "WindowsSupport" folder? What does it mean?

Reply

Answer 10

Oct 16, 2015 9:54 AM in response to Vadimster

Again, the same problem!

I downloaded the image windose 10 from a reliable site. Verify hash sums of two files. All hash sums matched after downloading.

I Launched the BCA and begin the installation again. Meanwhile a system downloading the windows support files. Started reloading and the choice of language. And again error: could not find driver...

I think that the bootcamp driveandosxresrveddiskis notbootableand thisproblemappeared.

Please help to resolve this probleme!

Reply

Answer 11

Loner T

Level 9

59,471 points

Oct 16, 2015 9:57 AM in response to Vadimster

You do not need to post the same on two separate discussions. 😉. Please use the other discussion.

Reply

Answer 12

Oct 16, 2015 10:01 AM in response to Loner T

ok sorry

Reply

Answer 13

Oct 16, 2015 2:49 PM in response to Loner T

An update after some time (and a long chat with an Apple support tech + a long and rather angry talk with two Applecare techs... + some pics sent to an Apple Engineer).

The problem doesn't directly come from the Win10 iso (I checked a number of time).

It come from some flaw in the new BCA process : the Win10 installation partition made by the BCA (OSXRESERVED - disk0s3 - temporary and erased at the following restart of El Capitan) is unable to properly function (somehow the AppleSSD is at some point not loaded correctly by the Win10 installer- You must give a proper driver from a external drive during the installation process - in my experience the driver found in the WindowsSupport.dmg worked).

It is funny that the windows installer lose the ability to read from the SSD drive when it booted from it.

It is unclear if the OSXRESERVED partition was made to be copied on a USB drive at some point (It didn't fully worked for me : I had to start from the internal drive (disk0) and load a driver from an external drive (disk1)

So it's not very clear if the responsibility is from MS (broken installer) or Apple (broken driver or partition scheme or else?).

But I find much more problematic that the "new BCA behavior" is not well documented on the website AND at Applecare. The news that BCA doesn't require an USB thumb drive anymore surfaced on a number of websites... But it appears to be not very well known by Apple technicians themselves. The lower Apple techs I talk to denied it (but a manager sort of admitted it after a while).

I had to SHOW them via VNC that the BCA never created an USB drive (even if I plugged one before or during the process...) nor give me the option to do it manually. The process was automatic from start to finish (Partition > Copy windows10.iso files in a hidden OSXRESERVED partition > Download drivers> Copy Drivers > Restart )... As a matter of fact they made me send some screenshots to document the problem...

You say that manually creating a partition with Disk Utility AND use of WindowsSupport.dmg drivers is the official method. But in fact it is not. I also had to show to the Apple technician the Windows10 installation pages on the apple website.

for a fresh install of Win10 on a fresh installed El Capitan :

- they encourage to download an iso directly from microsoft (the person I talked sort of denied it - ah ah ah)

- they encourage to use BCA.

- on the english pages they say "you may be required to use a USB flash drive" / on the french one they say "you'l have to use a USB flash drive". (apparently the french speaking technicians are prompted to follow outdated manuals just because it's not yet translated...)

Reply

Answer 14

Oct 16, 2015 2:57 PM in response to Renaud DERRIEN

So it turns outthe problem isa defectBCAOSXEl CAPITAN?

I wonder howwillthe events developaccording to the decision ofthis problem.

Reply

Answer 15

Loner T

Level 9

59,471 points

Oct 16, 2015 3:06 PM in response to Renaud DERRIEN

Renaud DERRIEN wrote:

It come from some flaw in the new BCA process : the Win10 installation partition made by the BCA (OSXRESERVED - disk0s3 - temporary and erased at the following restart of El Capitan) is unable to properly function (somehow the AppleSSD is at some point not loaded correctly by the Win10 installer- You must give a proper driver from a external drive during the installation process - in my experience the driver found in the WindowsSupport.dmg worked).

The AppleSSD64 (and AppleSSD.sys) is an unsigned driver in BC6. It is a well documented problem in [urgent]get "appleSSD.sys" error when installing windows 7 through bootcamp thread and elsewhere. W10 Driver Signature enforcement causes it to be not loaded causing problems during SSD functions. On older Macs, it can be safely removed. On 2015 Macs, it causes pain and grief. I have a bug report (22285185 - 21 Aug 2015) and provided documentation to Apple.

Reply