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I wanted to replace Mac OS X with Ubuntu completely so I put the Ubuntu .img on a USB drive and ran it and chose the

replace osx

option in Ubuntu's install menu. I realize this was a stupid way of going about trying to achieve this.

When I try to boot it says:

missing operating system.

I am currently typing this from Ubuntu via the:

try ubuntu

feature. According to GParted I have 3 current partitions:

  • fat32
  • ext4
  • linux-swap

The properties for each of those partitions indicate that only the linux-swap partition is "active" while the others remain "unmounted". I believe it is ext4 that holds the Ubuntu installation because GParted indicates that it has something installed on it, it is the largest partition and the other partitions have nothing on them.

If there is anything I can run in terminal to give you more helpful information, please let me know.

Thank you.

I have tried making a new partition table and then reinstalling ubuntu, but when that happens it still does not show anything as bootable and I will get the white screen but then, next, instead of getting a black screen that tells me there is no operating system, I get a flashing folder icon with an "x" in it.

share|improve this question

If you don't have anything valuable on your computer (anymore, haha), just grab the USB and boot it up again. At the install, select "Custom / Something else".

  • Delete all the partitions from your SSD/HDD.
  • You will need two partitions.
  • One Swap, which should be at least 4-8gb,
    (the less mem you have, the more swap you may need.)
    and One root.

  • One root: ext4, "/".

People often make a "/home" as well. It basically stores your files. Like Downloads, Pictures, Videos. So if Ubuntu decides to die one day, your files are still safe, and the system can be replaced in minutes.

It's up to you. (If you decide to have a /home too, then make the "root" partition ~30-40GB or so. Swap is again 4-8gb, and the rest goes for /home.)

share|improve this answer
You can press "New partition table" at the Install / Format screen to have your partition table re-set, and you can start from scratch. Both my answers and the new partition table WILL delete ALL the data on your HDD/SSD! – Shiki Apr 22 '13 at 14:10

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