can only boot windows using ALT and EFI BOOT on startup

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havinabubble Author

Level 2

155 points

can only boot windows using ALT and EFI BOOT on startup

Mac mini, 2 drives, Mojave macOS, Windows 10 peecee

successfully installed Bootcamp and Windows 10 on second drive... all was working well.

POWER ON would auto boot straight into Windows (what I wanted)

Went to repair the lack of audio on the windows side and from then on I cannot now auto boot

error "No bootable device -- insert boot disk and press any key"

I have to hold ALT and select EFI DRIVE and then it will work.

I've tried setting the STARTUP DISK under the mac side, no joy.

I cannot see a system tray icon for Bootcamp under Windows 10 side.

and I'm going round in an infinite loop trying to make a USB with the Windows Startup Repair Software via bootcamp under the Mac side (various errors each time, IF it will download at all)

Any suggestions?

TIA

Posted on Jul 11, 2019 4:38 AM

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Answer 1

havinabubble Author

Level 2

155 points

Jul 16, 2019 4:27 AM in response to Loner T

thanks I will when I get a second...

Interestingly I found another thread you took part in:

macOS Mojave 10.14.3 update broke Windows 10 bootcamp startup selection on MacBook Air 2018

https://discussions.apple.com/thread/250210742?answerId=250436908022#250436908022

and I recall that all was auto booting fine into Windows until I also did the latest Mojave update on the Mac side 10.14.5

since then it broke the auto boot.

While I do not wish to question your EFI suggestion or knowledge on this matter,

I'm left thinking that something simple got upset following that macOS update

If I set STARTUP DISK to Windows on the Mac Side, it fails with a black screen NO BOOTABLE DEVICE error

If I hold ALT and Arrow/Tab to EFI then hold CTRL (to get the circular icon) it will boot the second time with a blue Windows RECOVERY error - Your PC NEEDS TO BE REPAIRED message, and the three options are useless.

the only way to boot into Windows each time is hold ALT and select EFI manually!

Also the BootCamp control panel in Windows 10 ONLY shows me F key options...NOTHING else, should that be right?

Kind regards

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Answer 2

Loner T

Level 9

59,471 points

Jul 16, 2019 2:45 PM in response to havinabubble

havinabubble wrote:

thanks I will when I get a second...

Interestingly I found another thread you took part in:

macOS Mojave 10.14.3 update broke Windows 10 bootcamp startup selection on MacBook Air 2018

https://discussions.apple.com/thread/250210742?answerId=250436908022#250436908022

The MBA is a single-disk Mac. Your 2012 Mini is a server with two disks, which complicates the situation.

and I recall that all was auto booting fine into Windows until I also did the latest Mojave update on the Mac side 10.14.5

since then it broke the auto boot.

If there is a Microsoft directory in the EFI partition of BC disk, it should be recognized. We should check the BCD. Due to the two-disk setup, if the BCD points to a specific disk, but disk order is different, boot of Windows can fail. To test this, if you disconnect the disk which does not have BC, you can test the single-disk setup.

The No Bootable disk error can also come from the EFI firmware attempting a BIOS boot, when there is no MBR.

While I do not wish to question your EFI suggestion or knowledge on this matter,

I'm left thinking that something simple got upset following that macOS update

It is fine to question. No worries! MacOS update has been known to cause issues with legacy BIOS boot Macs, because it resets the MBR. It can also initialize the EFI partition.

If I set STARTUP DISK to Windows on the Mac Side, it fails with a black screen NO BOOTABLE DEVICE error

If I hold ALT and Arrow/Tab to EFI then hold CTRL (to get the circular icon) it will boot the second time with a blue Windows RECOVERY error - Your PC NEEDS TO BE REPAIRED message, and the three options are useless.

the only way to boot into Windows each time is hold ALT and select EFI manually!

This indicates that the EFI Boot is pointing to the incorrect device, in some cases.

Also the BootCamp control panel in Windows 10 ONLY shows me F key options...NOTHING else, should that be right?

Did you upgrade to Mojave from a previous version of macOS (High Sierra or older)?

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Answer 3

havinabubble Author

Level 2

155 points

Jul 11, 2019 7:04 AM in response to Loner T

Mac mini Server (Late 2012)

the server OS has been removed, its just a vanilla Mojave build now (on Server HD), and BOOTCAMP on the other.

as said previously it was working but something has changed and now it needs ALT and a manual select of EFI

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Answer 4

havinabubble Author

Level 2

155 points

Jul 12, 2019 7:18 AM in response to Loner T

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: Microsoft Basic Data BOOTCAMP 999.7 GB disk0s1

2: Windows Recovery 535.8 MB disk0s2

/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_APFS Container disk2 1000.0 GB disk1s2

/dev/disk2 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +1000.0 GB disk2

Physical Store disk1s2

1: APFS Volume Server HD 69.6 GB disk2s1

2: APFS Volume Preboot 46.2 MB disk2s2

3: APFS Volume Recovery 506.8 MB disk2s3

4: APFS Volume VM 2.1 GB disk2s4

/dev/disk3 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme +2.0 TB disk3

1: EFI EFI 209.7 MB disk3s1

2: Apple_HFS Time Machine Backups 2.0 TB disk3s2

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Answer 5

Loner T

Level 9

59,471 points

Jul 12, 2019 8:09 AM in response to havinabubble

A 2012 Mac does not correctly support EFI boot. It is a preUEFI Mac, so the Windows installation should use a BIOS/MBR overlay for the installation.

If you installed using EFI, it will cause issues with Audio and System Preferences -> Startup Disks will look for an MBR to boot from. Before your attempt to fix the Audio issue, was the installation mode EFI?

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Answer 6

havinabubble Author

Level 2

155 points

Jul 12, 2019 8:14 AM in response to Loner T

presume so... didn't change anything, the Bootcamp setup just did its thing.

Once setup and auto booting into Windows 10, I noticed there was no sound.

So I attempted (and struggled as I still am) to download the WIndows Support Software.

I finally got a folder onto a key manually, but the setup wouldn't run

found the Audio driver setup in one of the folders and ran that, sound returned, all was good.

But noticed the auto boot had stopped

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Answer 7

Loner T

Level 9

59,471 points

Jul 12, 2019 8:31 AM in response to havinabubble

The cleanest method to get the correct BC drivers is using BC Assistant -> Action -> Download to a USB2 Flash drive.

Once you run setup.exe, it will install AppleControlPanel.exe and many Apple services. From Windows, Are you able to switch back to macOS using the Bootcamp Control panel?

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