[SOLVED] Gparted and Disks reporting different partition tables


New Member
May 20, 2020
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Hi there!

I made a major goof and wrote a debian.iso to /dev/sdb (actually what I remember doing is writing it to /dev/sda but for reasons I'll get into shortly, my disk is reporting it differently.

As I understand it, that means that the first 430Mb or so (size of debian-10 netinstall) has been overwritten by the iso file

So here's what I've come up with so far:

I have 2 drives:
- an HDD at /dev/sda. It is used for my data. It had an NTFS and an ext4 partition (no OSes)
- an SSD at /dev/sdb. It has a windows partition and a few linux partitions. While I could wipe the linux paritions. If I had to wipe the windows I probably wouldn't be able to get it back (unfortunately I do still need to use it sometimes).
- on first error, the Bios was booting directly into the installer

using test disk:
- I don't remember the structure of the first 440 or so mB before I overwrote them. however, test disk appears to identify the partitions containing the OSes ok.
- test disk wouldnt let me use more than one logical partition so i had to make choose which partitions to "keep" in my new MBR
- After rewriting the changes to MBR using test. the BIOS no longer recognizes any bootable devices (but I can still boot into liveUSB)

using grub command-line (from a liveUSB, since BIOS can find the hard-drives)
- ls yields (hd0) (hd0,msdos1) (hd0,msdos0) (hd1) (hd1,msdos2) (hd1,msdos1) (hd1,msdos0) (hd2) (hd2,msdos4) (hd2,msdos3) (hd2,msdos2) (hd2,msdos1) (hd2,msdos0)
- ls (hd0) & ls (hd1) yield no response
- ls (hd2) yields debian-amd** (the name given to the usb .iso I originally overwrote the disks with)

from a liveUSB
- GParted and Disks report 2 different partition schemes for /dev/sdb
- Disks appears to show the partition table that I applied using testdisk
- GParted shows a single partition titled: debian-amd** same as what grub reported taking up the entire drive (no free space)

Finally, using gdisk:
sudo gdisk /dev/sdb
GPT fdisk (gdisk) version 1.0.3

Partition table scan:
MBR: MBR only
BSD: not present
APM: not present
GPT: present

Found valid MBR and GPT. Which do you want to use?
1 - MBR
2 - GPT
3 - Create blank GPT

I saw from some posts that the GPT table can causes issue for the BIOS at boot-time and the BIOS is clearly confused. What options do I have to try and straighten this out?

Thank you, take care
Al Gray

Disks reports a W95 FAT32 with contents: ISO 9660 (version Joliet Extension)

GParted recognizes the fs as ISO9660
Last edited:



New Member
May 20, 2020
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I was able to get some help on this issue over here:

based on the feedback. I will need to wipe my harddrive and reinstall everything :/
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