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