USB flash drives are great things, until they don’t work…
You store data on the flash drive. Then, one day you insert the flash drive into your computer – and get an error message. That’s what happened to David McCartney:
Once again I would be grateful for your assistance
I have been using a usb portable drive for the last year without any problems, but now I get the message that I have to format the drive before use.
Can you help?
I wrote back to David to suggest several possible ways to solve or identify the problem. I doubt that there’s anything wrong with the flash drive, but it is possible.
First, I suggested a full power-off shutdown of his computer – not just a reboot, not sleep, not hibernate – full power off. Then, turn on and try again.
A second alternative would be to try a different USB port on the same computer.
Trying it on a different computer would help determine whether the problem was computer-related or flash drive-related.
It is possible that he’s damaged the filesystem on the flash drive by pulling it out of the computer without doing a "safely eject hardware". Part of that function is to make Windows write any data that it still had in the OS’ file buffer. Windows might need to write several seconds after you thought the writing was complete.
I suspect that (1) he will find that the power off / power on will solve the problem, or that if it won’t work on his computer, that it will work on another computer.
If he does need to format it, that’s an easy step. Just put in in the computer, open Windows Explorer, right-click on the drive, and select Format.