Attempts to partition the drive failed, leaving it unbootable or inaccessible.
Some older USB drives had a “security partition” that required a password. If you lost the software, that partition remains inaccessible. Even low-level hex editors can’t see it because the controller lies to the OS. The AU87101A repack can issue the RESTORE_FACTORY command, removing all hidden partitions. au87101a ufdisk repack
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