I have tried everything, but nothing works...
Background: Started out with Windows 7, formated and installed Ubuntu and later installed Arch linux with a GPT partition table.
Running following commands from Ubuntu 12.04 Live USB.
Starting with: Have Arch Linux installed with four partitions. Using GPT.
/dev/sda1 Root partition
/dev/sda2 BIOS boot partition
/dev/sda3 Swap partition
/dev/sda4 /home partition
Step 1:
sudo parted /dev/sda
mklabel msdos
Get the "GPT signatures found"-error message then I check.
Step 2:
sudo dd bs=4M if=/dev/zero of=/dev/sda
Still get the error message.
Step 3:
sudo dd bs=1M if=/dev/zero of=/dev/sda
Still get the damned error message about GPT signatures found.
Step 4>
sudo parted /dev/sda
mktable msdos
I'm not giving up! Even this doesn't work, and the error message appear.
Output from sudo fdisk -l:
Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x0004cb5a
Device Boot Start End Blocks Id System
WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sdb: 2103 MB, 2103443456 bytes
255 heads, 63 sectors/track, 255 cylinders, total 4108288 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x71bafca0
Device Boot Start End Blocks Id System
/dev/sdb1 * 0 1607679 803840 0 Empty
/dev/sdb2 1595952 1600495 2272 ef EFI (FAT-12/16/32)
WARNING: GPT (GUID Partition Table) detected on '/dev/sdb1'! The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sdb1: 823 MB, 823132160 bytes
255 heads, 63 sectors/track, 100 cylinders, total 1607680 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x71bafca0
Device Boot Start End Blocks Id System
/dev/sdb1p1 * 0 1607679 803840 0 Empty
/dev/sdb1p2 1595952 1600495 2272 ef EFI (FAT-12/16/32)
Output from sudo parted -l
Model: ATA ST250LT007-9ZV14 (scsi)
Disk /dev/sda: 250GB
Sector size (logical/physical): 512B/4096B
Partition table: msdos
Number Start End Size Type File system Flags
[GPT-Signatures-found error message]
What should I do to remove the last fragments of the GPT table? Trying to reinstall Arch again, but can't use cgdisk to create partitions.