How to avoid the most common cause of flash-drive corruption

How to avoid the most common cause of flash-drive corruption

Patrick Marshall answers your personal technology questions each week.

Q: Can flash drives fail or have file errors if they aren’t kept sufficiently charged?

— Name withheld

A: Actually, while flash drives are powered by the computer’s USB port when connected, you can’t charge flash drives.

The flash drive has a grid of transistors that are switched on or off to store bits of data. The power for switching the transistors comes from the USB port and once you disconnect the flash drive there is no onboard source of power. No power is required for the flash drive to retain that data.

That said, there are a number of factors that can put the data on a flash drive at risk. First, flash memory will eventually wear out. Flash-memory components lose their ability to store data after thousands of reading/write operations, and the projected endurance of flash drives depends on the specific type of flash memory employed.

Industrial-grade single-level cell memory can perform around 100,000 reads/write operations. Less expensive multilevel cell memory is limited to around 10,000 reads/write operations, though that’s more than enough for most consumers’ needs. Most consumer drives carry five-year warranties, though most users will find their data to be safe long after that.

Still, the limitations on reading/write operations mean that flash drives aren’t ideal storage for files you’re going to be changing frequently.

But there are also other factors that can corrupt data on a flash drive. Environmental conditions — especially high temperatures and high humidity — can shorten the life of these devices.

Probably the most common cause of flash-drive corruption is inappropriate handling by users. Specifically, removing a flash drive from a USB port — especially if it is in operation — without using the operating system’s ejection command can result in corrupt files. In Windows, you’ll want to right-click on the drive in File Explorer and then select “Eject.”

Q: In regard to your recent column about blocking robocalls on cellphones, is there a way I can stop robocalls on my landline?

— Dick

A: Nomorobo offers a free app for landlines using voice over internet (VOIP). You can check it out at 

As for landlines not using VOIP, you can invest in a robocall blocker device for less than $100. One such device is CPR V5000 Call Blocker, which lists for $89.99 on Amazon. You’ll also need to pay for Caller ID service from your phone company.

The device comes with a preprogrammed list of 5,000 numbers identified as robocalls, and you can add up to 1,500 callers to the list by simply pressing a red button on the device. I can’t attest to its efficiency in blocking calls, however, and since robocallers frequently change the numbers you may find yourself hitting the red button’s ceiling.

Another option is to check whether your phone company offers an “anonymous call rejection” service. That service will block calls from callers who block their caller ID, a tactic frequently employed by robocalls and telemarketers.