USB flash drive repair diagnostics

Because the device is telling the system it has zero usable sectors. A drive controller keeps a translation table — the map from logical addresses to physical memory cells. If that service area is damaged, the controller cannot rebuild it and falls back into safe mode, reporting zero capacity. The file system has nothing to do with it, which is why formatting, disk checks and repartitioning all fail: there is nothing to address. The only fix is reflashing the controller with a mass-production tool for that exact chip.

No, and it is better to know that upfront. The mass-storage class is on the protected list in the WebUSB specification — a page cannot connect to the drive even if the user grants permission. Browser file APIs work on top of an already mounted file system, and a broken drive does not have one. Resetting a controller, rewriting a partition table or flashing firmware from a browser is impossible by design. So this tool gives the diagnosis and the exact commands, and you run them on your own system.

Data first, always. Nearly everything that brings a drive back — formatting, creating partitions, flashing the controller — erases its contents. The correct order is: take a sector-by-sector image onto the computer's hard drive, pull the files out of the image with recovery software, and only then repair the drive itself. If the files are readable even partially, copy them immediately: the state of dying memory changes from one connection to the next.

An MPTool (mass production tool) is the factory utility used to program a controller on the production line: it lays out the memory, builds the translation table and retires bad blocks. It is written by the controller maker and works only with that maker's chips, often only with a specific revision. Hence the absence of a universal solution: first identify the controller (ChipGenius or Flash Drive Information Extractor), then match a tool to it via the tables at flashboot.ru or usbdev.ru. Anything sold as a "universal flash drive repair tool" is, at best, just formatting the drive.

Only if you do not need the files. That prompt means a service part of the file system is damaged while the data itself is usually intact. Formatting overwrites exactly that service part, and recovery gets markedly harder: files then have to be reassembled by signature, without names or folder structure. The right sequence is image, recover from the image, and only then format.

On Windows: Device Manager, drive properties, the Details tab, then pick "Hardware Ids" — you get a string like USB\VID_090C&PID_1000. Faster still is the single PowerShell command included in the tool's steps. On Linux lsusb is enough; on macOS use System Information, USB section. These codes identify the device on the bus, and the VID often points at the controller maker, which already tells you which way to search for a tool.

As something to carry files on, yes; as storage, no. A drive that once fell into safe mode or locked itself read-only did not do so by accident: flash memory has a finite write endurance, and the spare blocks that replace worn ones run out. After a reflash the capacity is often smaller than the original — that is the retired memory. Keep only copies of things that exist elsewhere on such a drive.

The test works with a healthy drive: it writes and re-reads blocks to find fake capacity and bad areas, and it needs a mounted file system. This tool is for the case where the drive never gets that far: it is not detected, shows zero, or demands formatting. If a repair brings the drive back, running the test afterwards makes sense — it shows how much of the memory is genuinely alive.