usb stick is "READ ONLY FILESYSTEM"

Sometimes USB drives like the one I assume you're using have write locks, little switches on the drives themselves that you can toggle back and forth, kind of like the old floppy drives. If it's set to locked, you might see this kind of error.

Monkeymeetsrobot's suggestion is the first thing I would have suggested myself -- your original post made no mention of no write-lock switch -- many flash drives have them -- one of mine does and when locked would exhibit that behavior and the other one that doesn't, it still works properly.

That said, now that we know that yours doesn't have a write-lock switch, maybe you could try this:

It's a long shot, but what happens when you launch Terminal and type
ls -ld /Volumes/{usbStickName}?
If the permissions are not drwxrwxrwx, then, perhaps, from an admin-privileged account, you could
sudo chmod 777 /Volumes/{usbStickName}
and with any luck, you will have write privileges again.

Something to try....no guarantees....

Short of that, you may be giving your friend a slightly used usb flash drive as a Christmas present.


(if this solves your problem, or is actually helpful towards arriving at a solution to your problem, please consider marking this reply as "helpful" or "solved," in addition to, if applicable, marking this question as "answered")

darn it. sorry to hear that doesn't work! Well, I guess that's one Christmas present you don't have to buy for your friend now....

Hi Sepoe,
As a variation of j.v.'s suggestion, try the following command:

ls -loed /Volumes/<usbStickName>

If the stick has been used on a windoze machine it may have have an ACL on it.
--
Gary
~~~~
The sooner you fall behind, the more time you have to
catch up.

In addition to the previous suggestions, you might open the drive in Disk Utility. Select the USB flash drive and look at the lower left corner. If it says "Ownwrs Enabled: No: then the problem can be fixed with the info window for the drive. If it cannot be fixed, there may be a corrupt drive database:

/private/var/db/volinfo.database

The database file may be missing a return character causing two lines to run together. That could cause the problem you are seeing.

Try the Terminal command "mount" and check for the read-only option on the line for your USB stick. Mine lists

/dev/disk1s1 on /Volumes/KINGSTON1GB (local, nodev, nosuid)

which is not read-only. (Check the options inside the parentheses).

I was thinking something like

sudo mount -u -o rw /dev/disk2s1

in the Terminal would help, but that didn't work for me when I just tested it... (I tried going the other way, from read-write to read-only, but got a device busy error).

Maybe someone else can help you.

Hi Sepoe, Jarik,
Along the lines of what Jarik suggests and considering the command used in single user mode to make the boot drive writable, I suggest that you try the command:

sudo mount -uw "/Volumes/USB DISK"

I don't think it will work though. The system tries to mount it read/write in the beginning so if that failed, there's something about the stick that no system likes. I'm guessing that it simply isn't fully functional anymore.
--
Gary
~~~~
Isn't air travel wonderful? Breakfast in London, dinner in New York,
luggage in Brazil.