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I have installed windows on a 500GiB Seagate SATA Disk, (on a new EFI computer) and once windows was all setup, I plugged my Ubuntu (11.10 x64) HDD in and booted it. All works fine, apart from when I try to access data from the windows partition:

View from disc manager

**WARNING**: The partition is misaligned by 3584 bytes. Thus may result in very poor performance. Repartitioning is suggested.

It doesn't appear to see the two (windows boot/recovery and windows system/data) partitions there. Is there any way that I can get the system to recognise (mount) the partition(s) without re-installing Windows?

EDIT: GParted appears to pick the partitions up, but complains: View from GParted Oh, and /etc/mtab does exist.

EDIT2: Booting from a 11.04 x64 Live cd, The drive can be mounted through nautilus fine and GParted does not report any errors.

EDIT3: I ended up wiping and re-installing both OSes, as Ubuntu was doing this (which does not occur with a new, un updated install) and windows was refusing to boot with another drive plugged in. Thanks for the help!

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Are there any relevant messages in the dmesg output about the problem drive? – James Henstridge Apr 17 '12 at 4:54
@JamesHenstridge It doesn't look like it, just the same messages about the drive Ubuntu is installed on (because they are virtually the same device). – NRoach44 Apr 17 '12 at 4:59
I'm not sure what you disk structure is. Perhaps you could list the result of df -h and sudo fdisk -l? Do you have these problems if you boot from a Live CD/USB? What version of Ubuntu are you working with? – irrational John Apr 17 '12 at 5:01
@irrationalJohn Added those details, see edit 2. My Ubuntu (250GiB SATA) is sda. Windows is sdb. fdisk -l returned an interesting message: WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted. – NRoach44 Apr 17 '12 at 5:13
There shouldn't be any problem accessing GPT partitioned disks. Since it is a USB drive, perhaps try unplugging it and then replugging it and edit the question to include every new entry in the dmesg output. – James Henstridge Apr 17 '12 at 7:33

Your problem may be that the system tools on the Ubuntu on your 250 GiB SATA may be out of date and not know how to work correctly with GPT. The fdisk in my Ubuntu 12.04 had no problems with a GPT partitioned drive. I am using fdisk (util-linux 2.20.1).

You might want to do the following just to see what sort of updates might be available for the version of Ubuntu you are using. Upgrading might fix your problem.

sudo apt-get update
sudo apt-get -V --dry-run upgrade
sudo apt-get -V --dry-run dist-upgrade

If you don't want to apply all the upgrades which are available you might see what just upgrading linux utilities might entail.

sudo apt-get -V --dry-run install util-linux
share|improve this answer
I can't test it now, but I can assure you I had all of the relevant packages installed and updated (the fact that it works on a fresh install points at something else...) Thanks anyway! – NRoach44 Apr 17 '12 at 13:26

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