Have this problem. My USB drive got infected by virus which made most of the files and all of the folders disappear. I know that the files and folders were not deleted and are still in the USB for the drive's used space is still the same. I let my friend disinfect my USB using his NOD32 AV. The problem is after that, my USB won't get detected anymore. It doesn't auto-detect and I can't see the drive in Windows Explorer. I tried several PCs to no avail. I have several questions: Did deleting the virus make my USB undetectable? Is that a virus or a trojan? Can I still access my USB and retrieve the files and folders? Help anyone?