Itís a brand new 16GB sandisk Cruzer USB drive which is creating a problem. The next moment I bought this USB drive I tried coping 12.5GB worth of .iso images just to make sure that the drive is working well and fine but seems like my testing failed. The coping was going on successfully till a huge 3.5GB file copied after that my windows 7 started giving me messages and reports saying that the device is read-only. After that no coping took place. All the files which were lined up for coping after that 3.5GB file were failed to transfer. I have completely failed to make the drive writeable or change anything to the drive. Is there anyone who can help me out in some way at least?