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I'm using a full 2GB USB. Now it is automatically write-protected. I can't delete, add file or format the USB. I always safely remove before removing it. I have tried both editing regedit and diskpart as instructions on the internet. I have also scan it with a trusted antivirus. Please help me. I'm thinking of a person blocking my USB for money :(. Thanks for your help. P/s: the drive's type is currently FAT.