So, I got a problem while installing Ubuntu 16.04. I shrunk my HDD with 100 GB, as you can see here: click. But when I try to create a root directory and swap/home directory, as a lot of tutorials recommend, it won't work. I can dedicate 90 GB to the root, but the other 10 GB is now marked as unusable space. I looked around on the internet and didn't see a clear answer.

Quick question: if I install Ubuntu in this free space, how will I boot when I restart the computer? Boot menu or do I have to place the DVD in my computer if I want to use Ubuntu?

  • I think what you need to do is expand the original partition (in Windows) and let the Ubuntu installer handle the partitioning after you tell it how much space you want your Ubuntu install to have. When you install Ubuntu, it will install grub, which will detect whether there are any Windows installs, at that point Grub will give you a choice of which OS you want to boot into upon restart/startup. – TheXed May 9 '16 at 15:41
  • You have one available primary partition. And with MBR partitioning you have 4 primary partitions, but if you use one primary partition as the extended partition, then you can have as many logical partitions as you want "inside" the extended partition. So create an extended partition, then two logical partitions / (root) and swap. help.ubuntu.com/community/HowtoPartition – oldfred May 9 '16 at 16:00
  • @TheXed I believe letting Ubuntu handle all the resizing is NOT preferred method – pfeiffep May 9 '16 at 16:07
  • Preferred by whom? – TheXed May 9 '16 at 16:25

The default Ubuntu will install GRUB [Grand Unified Bootloader] replacing Windows bootloader. GRUB will provide a choice of which OS from which to boot.

Since many different situations exist there are many guidelines to follow; I suggest using Ubuntu & Windows dual boot... Quote from the link

When a Windows installation already occupies the entire hard drive, its partition needs to be shrunk, creating free space for the Ubuntu partition. You can do this during the Ubuntu installation procedure, or you can see How to Resize Windows Partitions for other options.

This link contains required and optional partitions. Quote from the link

The easiest partitioning scheme, on a non-GPT disk, is simply a root partition and a swap partition.


A possible cause for your problem is this: Your hard disk is partitioned using MBR, which only allows four primary partitions to exist. That is why, once you create one partition for Ubuntu, the limit is reached and the rest of the space becomes unusable. A workaround for this limitation is creating an extended partition (a partition that can contain an infinite number of partitions, but only counts as one). Unfortunately you need a bootable partition to install Ubuntu on, and extended partitions are not bootable.

If you want to install Ubuntu you will have to get rid of that Recovery Partition to make room (you can make a backup of it using Clonezilla) , or alternatively, install Ubuntu all on one partition, using a swap file instead of a swap partition (read Four-step Process to Add Swap File here).

Also, as others have said you won't need the DVD to boot, GRUB will ask you which OS you want on each boot.


I'll look into the first problem and update this answer accordingly.

As for the second question, no, you will not need to insert the DVD to boot Ubuntu as it will install GRUB to the MBR.

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