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Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
Hi guys,
I know a lot of people have been having troubles with bootcamp after installing High Sierra, not being able to install Windows, or not being able to boot into the mac partition when they were using the windows partition using bootcamp, but my situation is a bit different, I think.

I have a Mac Pro 2010, I used to have a Mac Pro 2009, I simply took my SSD out (I had Sierra and a fully working dual boot situation with Sierra and Windows 7 using bootcamp) and put it in my Mac Pro 2010. The « new » Mac Pro had a PCIe SSD already inside that wasn’t seen by Sierra so I had to upgrade to High Sierra. And here started all my troubles. After the upgrade, I’m not able to boot into Windows anymore.

On top of that, of course, to complicate matters, I have a NVIDIA graphic card, which is unflashed, and prevents me from using a bootcamp manager. It was never a problem until then.
Anyway, seeing that booting into windows from bootcamp (selecting my windows partition to restart the system) let to infos about my graphic card, like usual, and then a black screen with a blinking cursor on the top left of the screen and nothing happening, I felt something went wrong. I booted again, same thing. Because I’m lazy AF, I took out the SSD and attached it to my Mac mini and started the Mac mini with alt, to be able to start on the Mac Pro system from there. I booted into the mac partition and there, selected restart as mac. Still, I got the black screen when I put the SSD back into the Mac Pro. Laziness has its limits so I switched to the original old graphic card to see what was wrong. Still not mean to get to the drives. After resetting PRAM, I finally got to the boot manager, and was able to boot into mac.
From there, I restarted into the PC mode, to see what I could do. Same thing with the black screen and blinking cursor.
Obviously, my windows partition is still there, I can see it, with all the files names, windows, program files, etc. I don’t think the MBR was tampered with in any way. I haven’t tried booting to windows while on the Mac mini, that’s one thing I could still try.
But everytime I tried booting into the windows partition from the bootcamp manager, it ****ed my computer to the point that I had to reset the PRAM to get the startup manager back.

What do you think went wrong? I could, of course, reinstall windows, I don’t have that many things there, I’ll miss my Tomb Raider 2018, but it was a brand new windows install so I don’t really care, but the fact that I’m getting this weird blinking cursor tells me it’s a whole other level of trouble. And from what I read, with the new file system, even if I get windows working, I won’t be able to get back to my Mac partition from there because windows won’t be able to see it.

I can obviously get rid of the PCIe SSD and sell it, it’s a 500Go SSD... But if there’s a simple solution where I can keep everything inside the computer and make it work, I’d rather try it first.

Thanks!
[doublepost=1557919229][/doublepost]Here's a screenshot of my diskutil list. I feel there's something weird happening here... My "bootdrive" is my mac partition, "bootcamp" is obviously my windows partition. But Apple_APFS Container Disk4 is also my mac partition (bootdrive). I don't know why there's a "synthesized" disk listed, that's the first time I see something like that. I saw somewhere on the forum the "bless" method for the windows partition but I have no idea how to apply it here with this weird mix up of disks.
My PCIe disk is appearing as external.

diskutil.jpeg
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
What do you think went wrong? I could, of course, reinstall windows, I don’t have that many things there, I’ll miss my Tomb Raider 2018, but it was a brand new windows install so I don’t really care, but the fact that I’m getting this weird blinking cursor tells me it’s a whole other level of trouble. And from what I read, with the new file system, even if I get windows working, I won’t be able to get back to my Mac partition from there because windows won’t be able to see it.

Where did you get Tomb Raider? Basically any store will allow you to download a new copy on demand. You can delete and reinstall games as much as you want, and there's often cloud syncing of save games, like with Steam Cloud, so you won't lose progress.

Here's a screenshot of my diskutil list. I feel there's something weird happening here... My "bootdrive" is my mac partition, "bootcamp" is obviously my windows partition. But Apple_APFS Container Disk4 is also my mac partition (bootdrive). I don't know why there's a "synthesized" disk listed, that's the first time I see something like that. I saw somewhere on the forum the "bless" method for the windows partition but I have no idea how to apply it here with this weird mix up of disks.

The synth disk isn't weird at all.
As you can see on the drive formatted das APFS, it notes the volume as being a "container". Think of the meaning of that word. That container is seen in disk utility as a separate disk, namely the synthesised one. A single APFS container can hold multiple logical volumes, and even be spread across multiple drives - this is how Fusion Drives on APFS work too.
The single container in this instance, contains the Macintosh HD volume, the recovery partition, the preboot partition and VM. All inside a single logical volume.
The synthesised drive is not a physical disk, but a peek into the APFS container, whether it resides on one or several disks.

The bless command works the same as it would without a synthesised disk in the midst.

Though I have a question. If you hold Option during boot, is Windows similarly inaccessible, or is it only when trying to launch it through macOS?
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
It's not a problem getting Tomb Raider, it's that I finished the game and I was onto my last missions ^^ Just a few more things to do to get to 100% completion :) I'll lose all progression. But it doesn't matter that much, it's just a game and I finished it already.

I don't know which disk I should "bless" and which command to use exactly. disk1s3 ?

I can see windows if I hold alt during boot, and I can also see it when I go into the startup preferences in macOS. The problem is that after clicking it, I'm getting the normal startup with the infos about my graphic card and then it goes all black with the blinking cursor.
It used to do that for a few seconds and then I would see the windows bootup screen. Now, nothing is happening. It's like it's lost and doesn't know where to go.

(and on top of that, unrelated, but just to ruin my day, my apple cinema display 30" died on me so it was just the ********* day. I'm now using my cintiq as an external monitor, which is not the greatest thing in the world. And all of that started because I needed the Windows partition on my mac to run Avast on my PC SSD which got a nasty virus and wouldn't boot anymore... Chain of events, I get the virus on the PC, PC becomes unusable, I take out the disk, I decide to boot the mac in windows mode (mac is new, I just upgraded and sold the old one five days ago, keeping my original SSD. I of course tested it before but didn't think to test the windows partition), the screen stays blank, I realise my screen is dead, I switch to the cintiq, I realise there's a problem with bootcamp... Finally I ended up using my macbook pro to save my PC so at least that part is solved but still, worst. day. ever.)
 
Last edited:

treekram

macrumors 68000
Nov 9, 2015
1,849
411
Honolulu HI
I don't know if your problem is the same as what I just experienced. In my case, I installed Windows XP on a 2009 Mac Mini using Boot Camp. After installation, the Windows logo appeared and then it went black. Windows was working because when I shut down using the power button, it played the Windows shutdown chime.

In my case, I had changed the screen resolution before installing the Apple Windows drivers. So I was able to fix my problem by going into Safe Mode - pressing F8 after startup (you have to make sure it's set to boot in Windows) and then telling it to use VGA mode. From VGA mode I was able to redo the graphics adapter configuration. While your problem may not be the same, you should try safe mode - there are various options - maybe one will work for you. If the graphics card changed between the systems it was installed in, I think there's a good chance it will work in VGA mode.
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
It's not a problem getting Tomb Raider, it's that I finished the game and I was onto my last missions ^^ Just a few more things to do to get to 100% completion :) I'll lose all progression. But it doesn't matter that much, it's just a game and I finished it already.

Well, if it's through Steam it has Steam cloud for storing save games.

I don't know which disk I should "bless" and which command to use exactly. disk1s3 ?

I can see windows if I hold alt during boot, and I can also see it when I go into the startup preferences in macOS. The problem is that after clicking it, I'm getting the normal startup with the infos about my graphic card and then it goes all black with the blinking cursor.

In that case I don't think blessing it will make a different. Bless sets the disk to be bootable, but if it's visible from the boot-picker as well as macOS, it's clearly already detecting as being bootable. But yes, disk1s3 would be the one to bless if it were the issue.

As treekram mentions, I suggest trying to boot Windows in safe mode. AFAIK on Windows 10, the only way of booting safe mode if you can't get into the OS, is to just keep trying to boot until it automatically shows a screen with boot options. And this relies on Windows being started up enough to know you're trying to launch it. There should likely be another way, but I don't know it. On macOS you hold shift during boot; Guess you could try that.
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
I tried booting in safe mode. Apparently it doesn’t even go that far. I think it doesn’t actually find windows after it starts. I was getting some bios like infos when I had the Nvidia graphic card inside, and when it was time for windows to take it from there, that’s when I got my cursor of death.
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
I tried booting in safe mode. Apparently it doesn’t even go that far. I think it doesn’t actually find windows after it starts. I was getting some bios like infos when I had the Nvidia graphic card inside, and when it was time for windows to take it from there, that’s when I got my cursor of death.

I'd like to see the GPT for the disk to further debug this. Could you install gdisk (I don't think it's installed by default - If you know how to use homebrew it can be gotten through it)?
Disable System Integrity Protection (boot internet recovery, open terminal and type csrutil disable). After outputting the GPT you can enable SIP again through the same steps, but using csrutil enable.

Now in a Terminal, run sudo gdisk -l /dev/disk1
Assuming disk1 is still the one holding the bootcamp volume.

Please note, if this shows anything weird, we'll likely need to make changes to the GPT if you want to avoid wiping Windows and starting over. - Modifying the GPT can be a bit scary if you're not very confident with Terminal and disk manipulation. The command I've given you so far will only print the GPT and not modify anything, but modifications can cause the whole drive to become unbootable and/or unreadable unless manually fixed again, if anything goes wrong.

Changes will first only be written to memory, and not disk so if you feel you mess up along the way you can always quit without changing anything, but once you tell gdisk to write the partition schema it's written.

I'm not trying to scare you away from it; I've used gdisk to fix a corrupted MBR schema in the past myself, I just need you to be aware of this so that any potential issues that could theoretically occur are known to you in advance; And this is all assuming I see the issue in the partition layout.

But anyway, gdisk -l won't change anything, it'll just let me diagnose the partition map.
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
I’ve already saved my MacBook Pro with gdisk, i totally trust that thing, it’s a marvel.
I’ll do that tomorrow, first thing. It’s past midnight here and I’m already in bed with the iPad, but tomorrow will be Mac Pro day. I was actually thinking gdisk could be of help here.

What I’ve identified so far as a “maybe” problem is that my windows is in uefi mode and it’s trying to boot in legacy and not booting. Wasn’t a problem for a year and a half and suddenly became one with high Sierra.
[doublepost=1557962864][/doublepost]Ok, in the end I was too eager to wait and I got out of bed to do the gdisk command.
Here's the output:

Code:
Found valid GPT with hybrid MBR; using GPT.
Disk /dev/disk1: 1000215216 sectors, 476.9 GiB
Sector size (logical): 512 bytes
Disk identifier (GUID): 382E679C-7420-4C96-ACF8-08C911F2DCE9
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 1000215182
Partitions will be aligned on 8-sector boundaries
Total free space is 661 sectors (330.5 KiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1              40          409639   200.0 MiB   EF00  EFI System Partition
   2          409640       500215807   238.3 GiB   AF0A  Bootdrive
   3       500215808      1000214527   238.4 GiB   0700  BOOTCAMP
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
I’ll do that tomorrow, first thing. It’s past midnight here and I’m already in bed with the iPad, but tomorrow will be Mac Pro day. I was actually thinking gdisk could be of help here.

Good that you're already familiar with gdisk. It's a wonderful tool indeed.

What I’ve identified so far as a “maybe” problem is that my windows is in uefi mode and it’s trying to boot in legacy and not booting. Wasn’t a problem for a year and a half and suddenly became one with high Sierra.

Right. I've only had personal experience with legacy mode Windows bootups on Macs. If I'm not mistaken though, if it's a UEFI WIndows setup, it should be expecting GPT partitioning, but BootCamp has set it up with an MBR hybrid schema. I'm not sure how Windows works with this, but I'd say it's probably always been like this, seeing as its standard for BootCamp to set it up like this when it creates the volume.

Here's the output:

I think we need to dig a bit deeper. Could you, again using gdisk, get it to print the MBR table that is stored within the GPT? I can't remember the exact series of commands, but you run gdisk on the whole drive without any flags, and just dig around until you find "print MBR table" or something like that.
MBRs are not allowed to contain more than 3 entries, unlike GPTs that can contain more volumes than you'll ever need. I suspect that the MBR implanted in the GPT might have grown 1 volume larger, now containing 3 volumes and being out of spec.
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
That's what the print command got me on Bootcamp partition:

Code:
Partition number (1-3): 3
Partition GUID code: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 (Microsoft basic data)
Partition unique GUID: 483B579D-03F5-41D9-A8C2-8F7F0CD1B685
First sector: 500215808 (at 238.5 GiB)
Last sector: 1000214527 (at 476.9 GiB)
Partition size: 499998720 sectors (238.4 GiB)
Attribute flags: 0000000000000000
Partition name: 'BOOTCAMP'

I don't know how to go any "deeper" inside the partition. I looked through the commands and not one seems to do that.
Printing the partition table got me that:

Code:
Disk /dev/disk1: 1000215216 sectors, 476.9 GiB
Sector size (logical): 512 bytes
Disk identifier (GUID): 382E679C-7420-4C96-ACF8-08C911F2DCE9
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 1000215182
Partitions will be aligned on 8-sector boundaries
Total free space is 661 sectors (330.5 KiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1              40          409639   200.0 MiB   EF00  EFI System Partition
   2          409640       500215807   238.3 GiB   AF0A  Bootdrive
   3       500215808      1000214527   238.4 GiB   0700  BOOTCAMP

but we're back to the beginning and that's not what we want.
 
Last edited:

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
That's what the print command got me on Bootcamp partition:


We aren't looking to dig into the partition itself;

The partition schema is GPT. The GUID Partitioning Table. But it's a hybrid! Inside the GPT is an embedded MBR (Master Boot Record), which is an older partitioning schema used by legacy BIOS systems. There should be an option to print the MBR. Likely under either advanced or recovery. If you can't find it, let me know and I'll run through the motions of disabling SIP to check myself :)
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
Ok, expert mode gave me this:

Code:
Disk size is 1000215216 sectors (476.9 GiB)
MBR disk identifier: 0xA2AEB115
MBR partitions:

Number  Boot  Start Sector   End Sector   Status      Code
   1                     1       409639   primary     0xEE
   2                409640    500215807   primary     0xFF
   3      *      500215808   1000214527   primary     0x0C

(sorry for the late reply, a friend visited unexpectedly yesterday and I couldn't decently park her in a corner while I was working on the computer ^^)
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
(sorry for the late reply, a friend visited unexpectedly yesterday and I couldn't decently park her in a corner while I was working on the computer ^^)


Absolutely no issue. People in physical presence take precedence.

I do however have both good and bad news. The good news is that as far as I can tell, your partition map for legacy BIOS boot to find Windows and hand-over boot protocol to Windows afterwards looks just fine.
The bad news is that I then have no more ideas as to what might cause your issue
 

Nessdufrat

macrumors regular
Original poster
Jul 19, 2015
164
36
Between France and Switzerland
Yes, that’s also what I figured seeing the result of that output :/
I’m feeling ready to reinstall everything but I just don’t want to get into the same kind of troubles later.
Also, once weird thing that I never had before is that sometimes, at boot, my fans go crazy for about ten seconds, before going back to a normal speed and boot is then starting normally.
I guess that would be SMC related, but I can’t understand why it would happen sometimes and not all the time.
I really hope there’s nothing wrong with that computer since I just sold my old one a week ago...
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
Yes, that’s also what I figured seeing the result of that output :/
I’m feeling ready to reinstall everything but I just don’t want to get into the same kind of troubles later.
Also, once weird thing that I never had before is that sometimes, at boot, my fans go crazy for about ten seconds, before going back to a normal speed and boot is then starting normally.
I guess that would be SMC related, but I can’t understand why it would happen sometimes and not all the time.
I really hope there’s nothing wrong with that computer since I just sold my old one a week ago...


Strange. Fan behaviour like that would usually point to a failing sensor or sensor connection.
I guess you could try and run Apple Hardware Test, but I honestly have no clue about this, and if it's intermittent anyway, it won't necessarily spot an issue even if there is one.
I wouldn't jump to conclusions that the hardware was at fault before having exhausted software related problem vectors though. From here on, I think an SMC reset and a reinstall is your best move, and hoping all the weirdness across the board will stop. ¯\_O_/¯
 

casperes1996

macrumors 604
Jan 26, 2014
7,593
5,764
Horsens, Denmark
I could do that.
Btw, I’m having issue with the SMC on a iMac, how do you reinstall that? Reset, I know, bypass, i know that too, but reinstall, i have no idea :/


I'm not sure you can - If the SMC software can be modified, it would go through Apple's firmware updater.
The firmware-updater is bundled with macOS updates inside the pkg. It's a command line tool that takes a path to a firmware folder as its argument, checks if it's newer than the installed firmware and if it is, writes it to a pre-boot partition of the boot drive, and sets a flag in NVRAM to update the firmware on the next boot. Strangely this flag only seems to be writable by the firmware-update tool by Apple, manually trying to change the flag in NVRAM doesn't seem to do anything.

The firmware-updater also has a flag that allows it to write the firmware code to the pre-boot even if it is not a newer release than the existing firmware, but when the system boots up, it won't update the firmware, as the existing firmware also checks versioning - The only way around that is to use a hex-editor to modify the version number of the firmware you want to flash, which can cause issues with future firmware updates from Apple.
 
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