This is the most technical but often the only solution for the AU87101A error. A "Mass Production Tool" (MPTool) is software made by the controller manufacturer (often Alcor, Phison, or SMI) to force-flash the firmware back onto the drive.
Warning: This will erase everything on the drive. Use this only after you have recovered your data (or if the data is worthless).
If the data is priceless (family photos, thesis, business accounts) and software fails, stop tinkering. Professional labs can desolder the NAND chip and read it directly. This costs $300–$1200. au87101a ufdisk
Q: Is AU87101A UFDISK a virus? A: No. It is a symptom of firmware failure. However, a virus can cause the corruption that leads to this error.
Q: I ran the MPTool and now the drive is even smaller (e.g., 32GB became 8GB). Why? A: The MPTool detected bad blocks on your NAND chip and "blocked them out." Your drive's usable cells have degraded. It is time to buy a new drive. This is the most technical but often the
Q: Can I fix this on a Mac?
A: MacOS will also show the drive as unidentified. Use Disk Utility -> First Aid. If that fails, you must use a Windows PC for the MPTool, as MacOS does not support these low-level USB flashing utilities.
Q: Does this work for SD cards? A: No, "AU87101A UFDISK" specifically refers to USB flash drives. SD cards have different controllers (though they can also show generic errors like "Generic Storage Device"). Use this only after you have recovered your
The AU87101A is a legacy but ubiquitous controller in the USB storage market. The associated ufdisk utilities represent a critical layer of low-level maintenance, allowing for the recovery of corrupted devices and the exposure of fraudulent flash memory products. Effective use requires precise matching of the software configuration to the hardware NAND specifications.
