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I'm trying to install Windows 7 x64 on my computer. I have four drives partitioned like this:

  • First drive: 128GB SSD with my Linux partitions + the 250MB Windows 7 boot partition (which apparently needs to be on the first drive)
  • Second drive: 3TB HDD with hybrid MBR, with a 1TB BIOS partition for my Windows 7 system and 2TB GPT partition for my data (I can't simply do all GPT because Windows 7 can't boot on GPT when it is not launched from UEFI)
  • Third and fourth drive: should be irrelevant, 2x1TB RAID1 for data

The setup DVD boots correctly, is able to detect all my partitions and seems to install everything correctly (no error in the installer logs). But then, after the first reboot, when Windows tries to boot from the disk, it hangs while loading "disk.sys" (according to the safe mode output).

I already tried several things:

  • Disabling legacy USB support in the BIOS: mentionned by several people online, did not fix the problem
  • Switching from AHCI to IDE mode and reinstalling: did not fix the problem
  • Removing the hybrid MBR stuff and using a simple BIOS partition table with only one Windows partition: did not work either, so this is probably not linked to the hybrid MBR.

Does anyone know how I could solve this issue and get my Windows to boot in order to continue the setup?

share|improve this question
Dangers and Problems of a Hybrid – Moab Mar 2 '12 at 16:20
@moab as I mentioned in my question, I tried removing the hybrid MBR and the same problem occurs – Pierre Bourdon Mar 2 '12 at 16:20

I managed to "fix" that by installing Windows on a spare hard disk. I'm still interested if anyone has a valid explanation about this problem.

share|improve this answer
Please provide it for completeness, and you will be able to accept your own answer within 24 hours. Also, just an FYI: Never switch from AHCI to IDE mode (or vice-versa), or Windows won't boot up. That being said, I'm glad you found the solution, and would love to read it. – Breakthrough Mar 3 '12 at 23:50

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