Some people eat, sleep and chew gum, I do genealogy and write...

Tuesday, December 24, 2013

Flash Drive Disaster -- Genealogists Beware!!!

A common sight at FamilySearch Centers and other places frequented by genealogists is the researcher with a flash drive around his or her neck on a lanyard. I'm also fully aware that many genealogists use their flash drive as a primary backup device. This is not all bad since flash drives are reliable and relatively secure ways to store data files. However, there is a setting on all flash drives that can make saving files subject to risk of losing all of the data. This problem was called to the attention of the missionaries and volunteers at the Mesa FamilySearch Library by one of the directors, Adrian Kuzdas in a memo. Adrian formerly worked for Microchip Technology as the vice president of Microchip's Security, Microcontroller and Automotive Division and has first-hand knowledge of the flash drive manufacturing processes. According to Adrian,
To boost performance on flash drives, the manufacturers provide the ability to cache memory between the drive and your host PC. Although this performance advantage is something most people would never need, there is a setting to allow it and it creates a potentially hazardous situation.

Manufacturers typically don’t enable this feature on drives they sell and leave that procedure to a knowledgeable user, but lately I have seen flash memory devices come right out of the blister pack from the manufacturer with that feature enabled…… very very risky.

When caching, the drive hangs it all out there for the PC to rapidly edit, but doesn’t write all the data back until you do a formal eject (you all do that don’t you??). Well, if there is a power glitch, or somehow you pull the drive out of the PC without the proper ejection sequence, guess what… the data WILL be corrupted (and generally not recoverable if you leave the host PC and move on).
I have been cautioned in the past to make sure that my flash drive was properly ejected before removing it from the computer. However, I have read a number of articles that give the opinion that removing the flash drive, as long as it was not in use, was perfectly okay. Apparently, those who wrote these articles were unaware of the problems caused by a premature removal of the flash drive. In fact, it is likely that some of the problems that we have experienced at the Mesa FamilySearch Library relate to this very problem. This occurs when a patron complains that they have lost the data that they thought they were saving to their flash drive.

I usually check my flash drive before I leave to make sure that all of the files that I've copied, or thought I had copied onto the flash drive, are still there. Adrian suggests the following procedures:
Check your drives to disable this feature:

1) Insert the drive into the PC
2) Click on My Computer or Computer and find the drive
3) Right click on the drive letter and left click on Properties (might take a moment)
4) Left click on Hardware and left click on Properties
5) Left click on Policies (some drives won’t have this… that’s good… you’re done!)
6) Make sure Enable Write Caching is not checked. Some drives will have a check box indicating that checking the box DISABLES write caching, then you want that box checked. Whatever it takes to assure that Write Caching is disabled!
7) Click OK

You are now MUCH MUCH safer with your data, but as always, be sure to back up anything you don’t ever want to lose. This is good sense common practice for all electronic media.
A word to the wise and a warning to the unwise.


  1. I'm glad someone raised this James. I see too many people just yanking their flash drives out of their computers without realising the risk. I do a formal eject all time -- even when I've disabled any write caching - just in case I'm using a new or unfamiliar drive one day. It's a little like getting used to pumping on the brake pedal in bad weather -- even when you have ABS braking -- just in case, but then I drive a 1964 car most of the time so I'm excused. :-)

    1. I got in an accident once when I had just gotten a new car with ABS brakes and pumped them to stop and the ABS stopped working and so did the brakes. No one was hurt however except the car was smashed.

  2. Thanks for the great and useful information James. I had no idea about the caching. I use external hard drives and other methods for backing up my data, but I do use flash drives often. I will pass this along. And, I can assure you I will be checking for that disabling feature.

  3. How does an amateur know how to check and correct this?