How To Solve: Cannot Write to Ext3 or Ext4 Partition


While installing fresh new Ubuntu 12.04, I created an extra ext3 partition exclusively for Linux usage along with my Root, Swap and Home partition. Problem occurred when I tried to copy something in that particular ext3 partition. I did not have write permission to it. I was surprised to know that I cannot create a folder in the ext3 partition.


When I looked at the properties of the ext3 partition, I found that the owner of the partition was root and not the default administrative user.


Since the owner was root, the obvious thing to do was to change the owner from root to my default user. I’ll give step-by-step procedure which I followed. The whole procedure is followed in terminal (Ctrl+Alt+T).

First thing, change the user to root:

sudo su

Now, identify the partition you are dealing with. Use the fdisk command to see the partitions, their sizes and their type. The output may seem like this:

root@note:/home/note#fdisk -l

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      206847      102400    7  HPFS/NTFS/exFAT
/dev/sda2          206848   215541759   107667456    7  HPFS/NTFS/exFAT
/dev/sda3       215544166   625141759   204798797    f  W95 Ext’d (LBA)
/dev/sda5       215544168   420340724   102398278+   7  HPFS/NTFS/exFAT
/dev/sda6       461080576   468891647     3905536   82  Linux swap / Solaris
/dev/sda7       468893696   625141759    78124032   83  Linux
/dev/sda8       420341760   461066239    20362240   83  Linux

The partition which was looking for was /dev/sda7 which I identified by its size (approx. 78 GB). Once you got the partition’s device number, its time to find out its UUID. Use the blkid command for that:

root@note:/home/note# blkid
/dev/sda1: LABEL=”System Reserved” UUID=”E400CABD00CA95C8″ TYPE=”ntfs”
/dev/sda2: UUID=”E61CD55A89D525F9″ TYPE=”ntfs”
/dev/sda5: UUID=”01CB76F7C25198FB0″ TYPE=”ntfs”
/dev/sda6: UUID=”d389de2d-3a6d-4ed7-94dc-c0f3d560e325″ TYPE=”swap”
/dev/sda7: UUID=”f920adf0-6018-4335-8314-4e1b79ca2d6b” TYPE=”ext4″
/dev/sda8: UUID=”a159c031-5f44-4187-b6dd-fea76235b36c” TYPE=”ext4″

In the above command I got the UUID of /dev/sda7. Now change the ownership. Use the following command:

chown username /media/Desired-UUID

Replace username and Desired-UUID with correct values. Unmount and mount the ext3 partition again. Enjoy full access to it now. Cheers :)