So the problem ended up being that by default the mounter that puppy used would only mount USB drives in read only mode. I added a setting to the /etc/fstab file that specified the file should be mounted in Read-Write mode and that fixed it.

Of course then I upgraded to the next version of puppy ...

So I've created a new user and assigned their home to an external drive mapped under /mnt/<drivename>. When I login using FTP from an XP machine I am able to see all the files, but I cannot upload new files. The error says something about not having permissions to perform the action. Is there a way ...