I tried to install Ubuntu on my Acer Extensa 5420 laptop. At the point where Gparted should allow me to select partitions I could not see my Windows partitions with Vista and XP installed on them. It was written that the disk has no operating systems installed.
After googling I found out that this behavior may be caused by SATA drive with suggestions to change settings in BIOS. My BIOS does not provide means to change such settings. Has anyone here encountered the similar problem? Any suggestions how to install ubuntu? I have two partitions on my HDD and about 35GB of unallocated space.
sudo parted -l resulted with Error: /dev/sda: urecognised disk label (that's the disk with windows), and correctly recognized ubuntu live usb drive.
sudo fdisk -lu /dev/sda returned nothing but prompt for the next command. When I boot Ununtu Live in "try" mode and run Gparted it sees only the drive with Live USB. It does not see sda drive. But the disk utility detects HDD with Windows.
Any help would be appreciated.
Update:
sudo fdisk -l lists only USB drive:
Disk /dev/sdb: 4005 MB, 4005560320 bytes
124 head, 62 sectors/track, 1017 cylinders
Units = cylinders of 7688 * 512 = 3936256 bytes
Sector size (logical/physical) 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00c875f
Devise Boot Start End Blocks Id System
/dev/sdb1 * 1 1017 3909317 c W95 FAT32 (LBA)
Update #2:
This is the output of list disk from Vista (I have moved unallocated space on the disk to one of the partitions since I posted my question here):
Partition ### Type Size Offset
------------- ------------- ---------- -------
Partition 1 OEM 10 GB 1024 KB
Partition 2 Primary 112 GB 10 GB
Partition 3 Primary 92 GB 121 GB
Partition 0 Extended 20 GB 213 GB
Partition 4 Logical 20 GB 213 GB
Update #3:
Here is the screen shot of disk manager:

diskpart, select your disc, and run thelist partitioncommand. – JdeBP May 24 '11 at 13:16