I installed Manjaro on my desktop computer which has multiple SSDs with one SSD having a Windows 10 installation. I tried to install Manjaro on a secondary SSD, which worked fine, but GRUB was unable to install as it was unable to find the EFI system partition (ESP) on the drive. I check manually and there was no ESP on any of the drives. I manually created a ESP as described in the Arch wiki and manually installed GRUB for EFI Systems as described in the Manjaro wiki.
The problem I have is that Windows 10 is not found by grub-mkconfig
and therefor not listed in the boot options anymore, only Manjaro is listed. I guess the reason for that is that the Windows installation still uses BIOS and not UEFI. If I read this Ask Ubuntu question correctly, I need to switch GRUB back from UEFI to BIOS so GRUB can find the Windows installation. What is the best way to archive this in a clean way?
My current drive setup is as following: sda (SSD with Windows 10 installation):
Disk /dev/sda: 232,89 GiB, 250059350016 bytes, 488397168 sectors
Disk model: Samsung SSD 850
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xb507cf23
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 1026047 1024000 500M 7 HPFS/NTFS/exFAT
/dev/sda2 1026048 487320175 486294128 231,9G 7 HPFS/NTFS/exFAT
/dev/sda3 487321600 488392703 1071104 523M 27 Hidden NTFS WinRE
sdb (sdb5 is the shrunk NTFS data partition, sdb2 Manjaro and sdb3 the manually created ESP partition).
Disk /dev/sdb: 1,82 TiB, 2000398934016 bytes, 3907029168 sectors
Disk model: CT2000MX500SSD1
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0x26b4b1bf
Device Boot Start End Sectors Size Id Type
/dev/sdb1 1985 1984962559 1984960575 946,5G 5 Extended
/dev/sdb2 1984962560 3905980415 1921017856 916G 83 Linux
/dev/sdb3 * 3905980416 3907028991 1048576 512M ef EFI (FAT-12/16/32)
/dev/sdb5 2048 1984841727 1984839680 946,4G 7 HPFS/NTFS/exFAT
Partition 1 does not start on physical sector boundary.
Partition table entries are not in disk order.
There is also a third NTFS SSD sdc which only holds data.