I just got a Dell XPS 17 that came with an SSD with Windows installed. I bought a second SSD to install Ubuntu 20.04 onto. After installing Ubuntu the first time using the default partitioning option everything worked fine except that grub would never appear so I would need to switch between the two in the BIOS. I tried reinstalling Ubuntu and used the 'something else' option to install and make my own partitions on the second SSD. Grub would appear fine but now I can't see my Windows SSD in the BIOS. In gparted it also labels the SSD as unallocated space.
I think I did most of what you're supposed to do to get the dual boot to work and I'll attempt to list some of the relevant things I've tried although I don't think I'll remember them all.
- I changed the storage settings from RAID to AHCI and set whatever Windows settings were needed to support that. I was able to get Windows to boot after making those changes and confirmed that it worked correctly through device manager.
- Disabled secure boot
- Disabled fastboot in Windows
There were probably some others but I'm not sure.
So the part that I'm really confused about that since installing Ubuntu the second time it's as if my Windows SSD is does not contain Windows anymore or at least it isn't recognized as bootable. I'm quite certain that I made no changes to the Windows SSD during the Ubuntu installation. But now both the BIOS and gparted don't recognize the SSD as having Windows on it. Additionally, while doing research on this a lot of people recommended for similar things that you make a manual entry in the grub settings. As a part of that you need to get the UUID of the SSD using blkid. However when I run blkid the SSD that should have Windows on it shows no UUID only a PTUUID. The exact entry is:
/dev/nvme0n1: PTUUID"<the PTUUID>" PTTYPE="gpt"
I'm not sure if that's relevant but I thought it was strange.
Sorry if this isn't too well formed, I've forgotten a lot of what I did during the last 4 hours and I'm not an expert with bootloaders. If there's any other useful information I can provide please let me know and I can update this post. Thank you in advance!