failed to partition

I've tried again and again, but I get two different errors. One is

Failed to partition the selected disk
This probably happened because the selected disk or free space is too small to be automatically partitioned.

and the second is

No root file system is defined
Please correct this from the partitioning menu

This is no "partitioning menu". So, how would I go about fixing these errors?

Zitat

Where are you trying to do this?

Installing OMV. This happens after the network hardware is detected. The partition stage before installing the system.

Zitat

He probably trys to install onto as USB stick which is not detected within the setup. Bam he gets that error...

Nope, trying to install onto an 80GB Samsung. I think this is the drive that is not detected.

Zitat von "ryecoaaron"

Try wiping the disk using gparted live or systemrescuecd first.

I booted a gparted live USB (can't get it to boot from CD) and deleted everything there so it was left with unallocated space. That didn't work, so I booted gparted again and this time formatted the drive as an ext 4 partition. That didn't work. Something curious that happened: with the gparted live session, it had a dialogue box that said "The backup GPT table is corrupt, but the primary appears OK, so that will be used."

I'm reading about repairing GTP disks, but I don't really understand (yet) these texts. I'm also reading about "defining a mount point" in a tutorial for Ubuntu. I don't know if that will help me. Another suggestion was to boot an Ubuntu live disk and use the command "apt-get remove dmdraid". Which reminds me; I've successfully installed OMV once before and put the disks in a RAID 1 array. Then I copied some stuff and the power went out. So I decided to reinstall and remove the RAID, but I ran into the current problem.

help?

Zitat von "ryecoaaron"

Boot gparted and execute these commands - change sdX to your drive:

dd if=/dev/zero of=/dev/sdX bs=512 count=1000
parted /dev/sdX mklabel msdos

This is the correct answer!

I booted a Lubuntu live disk (can be any Linux distro), then opened the terminal (Ctrl+Alt+t) and typed:

dd if=/dev/zero of=/dev/sda bs=512 count=1000
parted /dev/sda mklabel msdos

I noticed in the second of these two commands that msdos was used... I think my problem was that I was labeling (using gparted) the disk gpt.
However, I'm curious about what the first dd command did.

Thank you for your help!