fredronn: Well done! I have also had some problems with e10 not reading the file system, but that was because i installed the bootloader GRUB onto the first sector.
It is really a strange setup iriver has chosen. It's called superfloppy. Once the file system is not there, it's hard to format the disk so that the firmware is happy using main stream software. Ordinary disk partitioning software does not handle this. I had to use the mkfs gnu/linux command with the -F (force) option... Even though fdisk for gnu/linux seems to be built in into the firmware! That probably breaks the license of fdisk anyway.
It's also not possible to add partitions.
And it's not possible to install GRUB on e10 since that would break the file system.
I have hacked GRUB stage1 for that purpose, but then the real GRUB wont read the file system on e10 as well! Goddamnit!
shambolism:
Is e10 recognized by Windows, i.e. visible in My computer? If it is you should be able to format it. Choose FAT32, and the normal default settings for the other options. If it isnt visible, then you have trouble. Then you have to do some pretty advanced things that may be tricky for a newbie. I will help you if you ask.
If you want to read more:
http://en.wikipedia.org/wiki/Disk_partitioning