I was copying about 117 GB of files to a USB flash drive. The transfer reached roughly halfway before the drive suddenly disconnected. Since then, it has failed to work on my main PC, another computer, and different operating systems. Windows still shows something in Device Manager, but the drive does not appear in DiskPart. Could the drive be permanently damaged, or is there a way to recover or repair it?
1 Answer
The flash drive may have suffered a controller or memory failure during the transfer. Another possibility is that it has less real capacity than advertised, especially since it has no identifiable brand; counterfeit drives can appear to work until enough data is written, then disconnect or corrupt themselves. If it does not appear in DiskPart or as a usable disk on multiple systems, software repair tools probably will not help. Check its reported hardware details and, if the data matters, avoid repeated formatting attempts and consider professional recovery.

It has been working for years, but it is unbranded and there are no markings on it, so I cannot verify its manufacturer. I had previously used it without noticing any problems.