Files stored in my flash drive are always invalid

Mnkande Posts 1 Registration date Wednesday August 16, 2017 Status Member Last seen August 16, 2017 - Updated on Aug 16, 2017 at 09:54 AM
Hi, I can store files in my Samsung USB3 flash drive but when i open them; computer notify me that the files are invalid. For instance, when i open video, name of the video will just flick and nothing more. I tried to open in different Operating Systems like Linux, Windows 8, and Windows 7 but nothing improved. So what else should I do