macOS Sierra installed on external HDD USB3.0 not recognized in the bios boot menu

Hello Guys,

i have just installed macOs sierra on external HDD USB 3.0 and everything works fine, i have already windows 10 installed on another HDD (1TB), before i install Sierra i unplugged the windows 10 drive to make sure not to format it by mistake, after that i plugged both the external HDD and the windows 10 drive, i set the external HDD as a first boot, but every time the system booting it boot directly to windows 10, i checked the bios settings again and realized strange things, i have x5 boot options, 4 of them name as ''Mac OS X'' and the 5th is ''windows manager ( Windows 10 drive)'', i don't know where the bios read those boots??!, also when i unplug the windows 10 drive, and try to boot with macOS sierra it boot directly,

Note:Both windows 10 and Sierra installed UEFI mode,
So any suggestion would help me to dual boot, is highly appreciated.

Thanks in advance,

The "MAC OS X" BIOS listing problem is discussed in El Cap area. Basically, you need to boot into the Clover UEFI shell to delete the extraneous settings, save, reboot.

If you installed Sierra in UEFI with the UEFI bootloader then when you connect both drives the EFI files in their respective EFI partitions may be competing since there should only be one EFI partition, no matter how many drives you have installed, since EFI settings get copied to the BIOS. whew. Likewise, most here want Clover to control booting into OSes.

You'll want to re-read 'Going Bald''s guide, https://www.tonymacx86.com/threads/guide-multibooting-uefi-on-separate-drives.198869/

kiiroaka said:

The "MAC OS X" BIOS listing problem is discussed in El Cap area. Basically, you need to boot into the Clover UEFI shell to delete the extraneous settings, save, reboot.

If you installed Sierra in UEFI with the UEFI bootloader then when you connect both drives the EFI files in their respective EFI partitions may be competing since there should only be one EFI partition, no matter how many drives you have installed, since EFI settings get copied to the BIOS. whew. Likewise, most here want Clover to control booting into OSes.

You'll want to re-read 'Going Bald''s guide, https://www.tonymacx86.com/threads/guide-multibooting-uefi-on-separate-drives.198869/

Click to expand...

Thanks for your response, appreciate that, i will read the above guide again and i will be back with the results.
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i rechecked the guide again but honestly i don't understand what should i do, as far as i understood from you post, there are 2 EFI partitions, one for OSX and one for windows 10 and there should be one EFI partition for both, so how can i make clover control the boot for both systems?

Also, how can i delete any data restored in the bios related to the old OSX install?

mizo007 said:

i rechecked the guide again but honestly i don't understand what should i do, as far as i understood from you post, there are 2 EFI partitions, one for OSX and one for windows 10 and there should be one EFI partition for both, so how can i make clover control the boot for both systems?

Also, how can i delete any data restored in the bios related to the old OSX install?

Click to expand...

Do you have a Windows folder in your OS X drive EFI partition? Clover will not boot Windows if not.
Why worry about ti? You installed OS X on an external drive - just unplug it when you want to boot Windows.

Going Bald said:

Do you have a Windows folder in your OS X drive EFI partition? Clover will not boot Windows if not.
Why worry about ti? You installed OS X on an external drive - just unplug it when you want to boot Windows.

Click to expand...

Thanks bald for your time, appreciate that, i have managed to dual boot both windows 10 and Sierra and both boots and works fine, the only issue remaining is in clover boot menu i have around 7 or 8 partitions, most of them named'' Boot windows with legacy HDD 1, 2, 3, 4,... etc), i just realized that those partitions are from the old installation 3 years ago,

My question is is there a way to delete those partitions and keep only win10 drive and Sierra?

Also, the current clover boot theme is the last theme applied from last installation 3 years ago, i downloaded tony theme and added it in clove> themes folder and i modified the PLIST file, after reboot the old theme still exist, is there any solution for this?

Thanks in advance.

mizo007 said:

Thanks bald for your time, appreciate that, i have managed to dual boot both windows 10 and Sierra and both boots and works fine, the only issue remaining is in clover boot menu i have around 7 or 8 partitions, most of them named'' Boot windows with legacy HDD 1, 2, 3, 4,... etc), i just realized that those partitions are from the old installation 3 years ago,

My question is is there a way to delete those partitions and keep only win10 drive and Sierra?

Also, the current clover boot theme is the last theme applied from last installation 3 years ago, i downloaded tony theme and added it in clove> themes folder and i modified the PLIST file, after reboot the old theme still exist, is there any solution for this?

Thanks in advance.

Click to expand...

Doublecheck UEFI/BIOS BBS boot order. You might have a leftover EFI partition with Clover in it from previous installs.
Mount the EFI partition of every drive that has one and check it.

Going Bald said:

Doublecheck UEFI/BIOS BBS boot order. You might have a leftover EFI partition with Clover in it from previous installs.
Mount the EFI partition of every drive that has one and check it.

Click to expand...

I have deleted all the unused efi partition using EasyUEFI, but i believe those partitions are legacy which is not shows in easyUEFI as the windows in efi mode, i only see 2 boots entries when i launch easyuefi ( Windows manager and mac OS X), also i checked the Plist from CLOVER configurator under GUI> Customs entry and it's empty, i really don't know where those partitions stores currently,