I installed BT4r2 in a usb, i use unetbootin for make the usb-live, the instalations is OK the system run and I can use the system but the problem is when I will wana use the USB to saved however file and show me the next error

I into in the USB
root@bt:/media/cdrom0# touch hola
touch: cannot touch `hola': Read-only file system

The problem is not the permissions because would show this
juampix@bt:/media/disk-2$ touch hola
touch: cannot touch `hola': Permission denied

This problem never pass with other USB than i used, the USB that i use and with the that show the error is a "SanDisk Cruzer Blade 8 GB

Please somebody can say me some on this problem


Note:sorry for my english