I have an 8GB USB 2.0 flash drive (no-name), on which I tried a few days ago to copy a film of about 6GB. The flash drive had NTFS file system so I thought there will be no problems. But at some point an error had occurred that I didn't noticed and after some time I removed the flash drive without seeing the error. Now the flash drive is unusable.
I have a 16GB flash drive that stopped loading on either windows or linux after someone pulled it out of a windows computer without unmounting it first. After I couldn't repair it myself I took it to IT and they tried to chkdsk it, but it wouldn't run, they didn't tell me much.
At that point I gave up on data recovery and decided to reformat to at least have a usable flash drive again.