12.10 installer will not recognize partitions on sda (manual partitioning)

[kef_kf]

As the title suggests both ubuntu and kubuntu 12.10 installers will not recognize the partitions on my main hd.

When I select /dev/sda from the menu the installer prompts to create a new partition even though the hd has partitions on it that the live session can recognize and mount.

The same goes for gparted (which I assume is doing the partitioning in the installer), it also sees my hd as one big unpartitioned block.

[darkod]

Did you use that disk in fakeraid? Usually the installer ignores it when it has raid meta data left on it.

If this is the issue, you can remove the meta data from live mode:
sudo dmraid -Er /dev/sda

Another, worse, possibility, it an error in the partition table. In that case it can't display the partition but you wouldn't be able to read them in live mode too. Since you can read them, I think it's the meta data issue.