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I have an MDR disk with Windows 8 installed and system reserved partition. I have tried installing Ubuntu from both disk and USB, and it just cannot pick up on my partition table either way. It thinks I have an empty disk.

I tried formatting, installing Ubuntu, and then Windows, but the exact same problem happened - Windows could only see an empty disk. When I have Windows installed, Windows installation media can see my partitions fine, and the same with Ubuntu.

I'm guessing this is because my Windows disk refuses to install in UEFI, and my Ubuntu disk refuses to install in BIOS. Why is this? I thought that either could install either way without a problem.

In my boot menu, I am offered two options:

  1. SanDisk
  2. [UEFI] Sandisk

I assumed that the UEFI selection would install Ubuntu in UEFI, whereas the option without it would install in BIOS. They both seem the same to me, though - maybe I'm just being stupid.

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A disk that shows up as empty in the Ubuntu installer but that you know holds partitions is usually a symptom of one of two problems:

  • Leftover RAID data on a disk that's no longer being used for RAID. You can often get rid of such data by typing sudo dmraid -r -E /dev/sda; however, you should be 100% positive that you're not using RAID before you do this. Some computers come configured to use RAID, even for just one disk, and removing the RAID data in such situations without first disabling RAID in the firmware can cause problems.
  • Damage to the partition table. On an MBR disk (is that what you meant when you wrote "MDR disk"?), my FixParts program can often fix these problems, but that's not 100% guaranteed. If you've got a GPT disk or if FixParts doesn't help, you should post back with more information, such as the RESULTS.txt file created by the Boot Info Script. (You'll probably have to post this as a link.)
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