I have an external USB drive that I formatted with an msdos label and an ntfs file system. This was done as this drive is occasionally used to share data with a windoz box and I needed something compatible with windoz.
The initial mkfs and mount worked fine and I was able to put many files onto this disk (314 GB worth). Then I rebooted the Linux (ubuntu) system and now I can mount the disk but it is acting as if it is mounted read-only.
I cannot create files or directories on the device. I have umounted and remounted the disk several times explicitly specifying "-o rw" but the disk always acts like a read-only device.
I am doing all the copies, mounts, etc as root, and all the file and directories are 777 so I don't think it is a permissions problem.
When I attempt to touch a file (or mkdir, or cp, or cpio, or tar) here is what I get.
touch: cannot touch `jjv': Operation not supported
Any ideas???
Solution: Write error on ntfs file system on ubuntu 8.04
The ntfs volume might not have been removed clean the last time it was mounted in windows.
You can clear this by re-mounting it in windows, and using the "Safely Remove Hardware" option, or you can run checkdisk on it from windows, or you can even try using ntfsfix from ubuntu, although it isn't technically a full checkdisk.
If you are worried about data integrity I would try using the windows methods.