When I try to install Ubuntu 16.10 from a USB stick, the installer does not detect the presence of Windows 10. I would like to dual boot. Since I am a beginner, I have no idea how to make partitions. Is there anyway to get the installer to detect Windows 10?


Make sure that you have turned off quick startup in Windows and do a full shutdown by holding shift when you click shutdown to disable quick startup. If you dont do this, the Windows partition cannot be mounted by linux to see that there is a Windows partition.



I solved this issue for my own laptop after many hours. My problem was that the existing Windows installation used UEFI boot mode. So when I used rufus to install the Ubuntu 16.04 ISO image onto a USB memory stick, I needed to choose the "UEFI (non CSM)" option (rather than BIOS/legacy boot which was the default in rufus).

Then I had to boot my laptop from the USB drive (which in my case required first booting into BIOS setup mode and adding a temporary boot option for the USB drive), then install Ubuntu from the USB drive.

Only by installing Ubuntu in EFI mode was I able to get the Ubuntu installer to recognise the existing Windows installation and get it to create a dual boot menu with Windows and Ubuntu on it.

To check if Ubuntu is running in EFI mode (e.g. in try without installing mode), look in the /sys/firmware folder and there will be an EFI file if it is. Otherwise its running in legacy mode.


I know this is too late for OP, but for anyone googling, for me it was secure boot being the issue. I tried to disable secure boot initially via the BIOS, but for some reason the option was hidden behind CSM (which I later googled and found out meant Compatibility Support Module) which I disabled, and then I could disable secure boot. I was then allowed to install Ubuntu alongside Windows.


I just faced this problem on a new Dell XPS 8930. Even after disabling Secure Boot in the BIOS, the Ubuntu 18.04 installer failed to recognize the SSD at all, so it only offered a standalone installation. I came up with this somewhat devious workaround, installing Ubuntu on the 2TB drive that came with the system and borrowing some storage space from a second HDD that I had already bought to increase the storage capacity of the 8930.

In addition to the 8930 and the Ubuntu installation medium, you need one additional piece of software: Macrium Reflect, the disk imaging tool. The free version will work fine. Once everything is together and installed, follow these steps:

  1. Use Reflect to image the complete SSD into a file on HDD #2.

  2. Use Reflect to "restore" the SSD image onto the empty 2TB drive. If you want to ultimately move the Windows 10 boot to the HDD, you can take this opportunity to grow the Windows partition. This is recommended since Windows stores all kinds of crap on the system partition as it does upgrades, and over a period of years you will almost certainly run out of the piddling ~200GB of free space on the SSD's Windows partition. If you're going to keep using Windows on the SSD, there's no need to resize. You'll end up with 256G of the 2TB drive partitioned like the SSD, and the remaining space open and unformatted. This is where Ubuntu will live.

  3. Power down AND UNPLUG the system, and remove the SSD. This involves removing one small Phillips screw to release the SSD board. Check Dell's documentation if you're not sure what to take out.

  4. Boot into the BIOS, go to the Boot screen, and disable Secure Boot. This will automatically turn on Legacy boot support, which you'll have to turn off later if you want to turn Secure Boot back on.

  5. Pop in the Ubuntu installation medium and reboot into the F12 startup options menu. I used a DVD for installation, and there will be an entry on that menu that allowed me to boot the DVD using UEFI. I think a USB installer will automatically boot using UEFI; you might want to confirm that. Once Ubuntu is running, do the install. It will install onto the unused space on the 2TB HDD and recognize the Windows 10 installation you cloned there in step 2.

  6. Once Ubuntu is installed, you can dual boot between the Ubuntu and Windows partitions on the HDD. You can work this way forever, but if you want to use the SSD, power the system down and reinstall it. In my case, that was all it took - GRUB booted Ubuntu from the HDD and Windows from the SSD with no further configuration needed.

  7. You may want to do some cleanup after this. In Ubuntu, the HDD-based Windows disk shows up as a drive named OS; the SSD is completely invisible (there may be some fstab tweaks that will fix this, but I haven't looked since I don't care about accessing the Windows system drive from Ubuntu). In Windows, the SSD Windows partition shows up as drive C and the HDD Windows partition shows up as drive F. You could wipe out all those pesky extra partitions on the HDD and recover a quarter terabyte, or leave them there as a backup Windows partition that you can boot if a future Windows update breaks the actual Windows installation on the SSD. Just keep in mind that the HDD version of Windows won't boot and won't receive updates, so it will get old real fast.

You can try re-enabling Secure Boot, but I've run into a problem with Secure Boot where the Ubuntu boot hiccups when it switches over to graphics mode. It appears to freeze but if I suspend and wake the system everything is working. That's a problem for another day.

Sorry for the long-winded explanation, but it's a long-winded process. I figured I'd save everyone the few hours it took me to figure out this workaround.

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