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USB Not Recognized?: USB Recovery Case Study

USB recovery

The client in this data recovery case study had a USB thumb drive that no longer did anything when they plugged it in. The thumb drive was well and truly dead. Unfortunately, the client had been using the drive to store some documents, which were now gone—but not for good. There was still a chance that skilled USB flash drive data recovery professionals could recover their data. The client sent their failed flash drive to Gillware’s USB recovery specialists.

The NAND chip pulled off of the PCB in this USB recovery case

USB Recovery Case Study: Why Is Your USB Not Recognized?
Drive Capacity: 4 GB
Operating/File System: FAT32
Data Loss Situation: Flash drive completely stopped working—no response when plugged in, Windows cannot find device. USB not recognized at all
Type of Data Recovered: Documents
Binary Read: 100%
Gillware Data Recovery Case Rating: 10

USB Not Recognized? Why?

Once you get past the outer shell, your typical USB flash drive has four components. At its heart is the NAND flash memory chip itself, which holds all of your data. A controller chip manages the flow of data as it travels back and forth between the user’s computer and the NAND chip. The USB plug, of course, allows the flash drive to connect to your computer (or any machine with a USB port). These three components are soldered to a printed circuit board connecting them to each other. Any one of these components can fail and make a USB flash drive stop recognizing when you plug it in.

USB Not Recognized: The Usual Suspects

For starters, the USB plug itself doesn’t have the strongest of connections between itself and the PCB. Even a slight bump while the device is plugged in can damage the connection. Excessive physical trauma can sever it altogether. When the plug is damaged, the USB device can fail to detect altogether, or detect with an error message (such as error code 43) and prevent any further access.

The NAND chip itself can fail as a result of the cells holding your data naturally wearing out, or due to corruption of the data on the chip. Corruption can happen without any seeming cause due to normal wear and tear, or can happen if a flash device is mishandled while running. This can cause the USB drive to fail or appear unformatted. Aside from the glaring “Death Star exhaust port” weakness of the USB plug, flash drives are fairly resilient due to their lack of moving parts. However, if a NAND chip is subjected to enough force, though, it can crack or shatter, resulting in permanent data loss as the chip itself is destroyed.

The PCB itself can fail as well, especially due to water damage or an electrical surge. When the PCB fails, there’s nothing left to connect the disparate three elements of the flash drive together. This essentially “kills” the drive, since none of its remaining parts can talk to each other.

Many modern USB flash drives bundle all of these components together into a singular black device known as a monolithic chip. Although it appears to be a single chip, all of the normal components of the flash device still exist within it. The same components can still fail, although the monolithic chip lacks its predecessors’ glaring weaknesses and susceptibility to water damage.

Going Straight to the Source: NAND Chip-Off Recovery

In this particular USB recovery case, the flash drive’s PCB was the source of the client’s woes. Something had caused the circuit board to short out, although the client wasn’t sure what. Regardless of the reason, the result was the same. The USB flash drive was totally dead.

Many of the failed USB flash drives that come to Gillware’s lab have physical issues with the USB plug, which must be repaired by one of our skilled electrical engineers. These require the steady hand of an experienced data recovery specialist, but are relatively “easy” fixes. When the circuit board itself has died, the recovery process becomes more complex.

In these situations, our engineers carefully remove the NAND chip from the circuit board. Great care must be taken to avoid damaging any part of the chip, especially the delicate pins on its sides. With the chip removed, our engineers must connect it to a chip reader apparatus to read its contents. One nice thing about flash memory data recovery is that while NAND chips play much the same role as hard disk platters, a single NAND chip can be removed from its device and imaged using a relatively inexpensive adapter. No similarly-convenient equivalent exists for hard disk platters.

The real challenge comes next. All of the data on the chip is jumbled together like a jigsaw puzzle. It looks nothing like what data normally looks like when the user looks at the flash drive. It doesn’t even look like a sector on a hard drive’s platters. Normally, the controller chip pieces the data together properly. We can’t use the controller chip. But our NAND flash memory specialists can write custom software to do the controller’s job instead.

USB Recovery Results

Piecing together the raw data from a NAND flash memory chip is no easy task. But as long as the chip itself is unharmed, these recoveries tend to turn out extremely successfully. Our USB flash drive recovery experts managed to successfully recover all of this client’s documents from their failed USB drive. We rated this USB recovery case a perfect 10.

Will Ascenzo
Will Ascenzo
Will is the lead blogger, copywriter, and copy editor for Gillware Data Recovery and Digital Forensics, and a staunch advocate against the abuse of innocent semicolons.