I have a 256 gb flash drive. I plugged it into my USB port and it installed the drivers, etc. I then tried saving something to it and it wouldn't save. I formatted the flash drive and it saved fine after that.
I then moved approximately 30 gb of pictures onto the flash drive. They consisted of many folders and some 'loose' files. Once they finished moving, I made one master folder and moved them all into this folder.
I then set-up another master folder, and moved about 12 gb of files, mostly pictures, into this second master folder on the flash drive. I walked away from my computer while this operation completed. I came back after it was done and cleared some conflicts. It then completed.
I then tried to open the master two folders and they are empty. Upon checking, the flash drive still shows 44 gb of space used. I've opened and closed the drive, ejected and re-inserted the flash drive several times, and even opened it on a second computer. The same thing happens. It shows capacity at 249 gb, available space at 205 gb. When I open the drive it shows the two master folders, but the folders show empty. This was supposed to be a back-up for all my pictures, but now it seems I've lost them all.