While copying some large file I mistakenly taken out USB pen drive before the copy get completed.Later I again attached the USB pen drive in Ubuntu system but found that the USB pen drive showing read only filesystem message. I was not able to copy,create and delete any file.To solve this issue I followed some steps which I am sharing with this post.

To fix USB pen drive read only in Ubuntu,follow the given below steps

Step 1: Attach USB pen drive in system’s USB port. Automatically the Ubuntu will mount the USB pen drive and show icon on Desktop or Menu bar.

Open the terminal and become super user by running below given command

Step 2: First we have to find out in which directory the USB pen drive has been automatically mounted.For this run the df -Th command.
In given below output you can see,in my system the USB pen drive is mounted in /media/linux/C38C-099C,partition is /dev/sdd1 and filesystem is vfat.

Note: When you run df -Th command in your system,the USB pen drive may mount in different directory and the partition might also be different.Hence the output value which you will get, use the same values in further steps.

Step 2: Now unmount the directory in which the USB pen drive is automatically mounted . (As you can see mounted directory path in above ‘Step 1′)

Note: Replace the/media/linux/C38C-099C with the mounted USB pen drive directory path which is showing output in your system after running df -Th command.

Step 3: As we know the USB pen drive got /dev/sdd1 partition
and filesystem is vfat(see in Step 1). Now we will run dosfsck command to check and repair the filesystem

Note: The dosfsck command check and repair MS-DOS filesystems.Because the filesystem of USB pen drive is vfat hence we are using this command

Step 4: After the dosfsck command get completed.Remove the USB pen drive from system and then re-attach back to system.Now your USB pen drive should working and it should not have read only filesystem.

Note** After mounting the USB pen drive you may see a new file with extension .REC which was created because of dosfsck command.