I've never had any problems with flash drives until recently when I purchased a 64GB and a 128GB. My PC doesn't recognize either of them. The 128GB worked off and on but now, no matter if I put it in a hub or into a USB port, neither of them will come up. I hate to say it but I'm done with flash drives as I had a lot of important items on them and when I saw the big one going bad, I hurried up and moved as many documents as I could before it quit working again. I read where a lot of companies aren't loading them right so they're bound to give out sooner than later. What happened to the good ole days..... - I've used flash drives all my life but ever since I installed Windows 8.1 I've had all sorts of problems. I never spent this much time trying to keep my computer going when I had Windows Vista or Windows XP. Almost every day I have some sort of problem that pops up despite my efforts to run my scans and do what I can to keep my PC optimized ..... starting to get very depressing.