How To Repair An Unreadable USB Stick

Posted August 15, 2011 10:00 am by with 2 comments

At certain times you may get "adventurous" with your USB stick and do something to it which makes it unreadable – meaning to the point where you can’t even format the thing anymore. It also could be you have a USB stick so old that it has a really difficult time initializing.

Should you toss the stick out at that point? No, there is one more thing you could try – a low-level format.

Now I know – and so should you – that low-level formatting goes into danger territory when it comes to media storage. A low-level format has the same danger level as, say, flashing a BIOS. What this means is that if the process is interrupted, it can permanently ruin things.

A free utility you can download right now to perform a low-level format on a USB stick is the HDD LLF Low Level Format Tool. It’s speed-capped to 50MB/s unless you pay $3.30 – however it’s completely free to use otherwise.

The way this utility works is very easy. Plug in your USB stick and launch the program. Choose the LOW-LEVEL FORMAT tab, pick the appropriate device, and format.

I tested the utility on an old 512MB Sandisk Cruzer Micro I have, and this is what it looked like when running:

image

It’s important to note that once finished the stick isn’t usable yet as you will have to high-format it. All you need to do for that open up Computer (or My Computer if using XP), locate the drive letter assigned to the stick, double-click it and Windows will ask if you want to format the device so it can be used.

I do suggest not performing a quick-format just to be on the safe side.

Will this work on storage devices other than USB sticks?

Of course it will. It will work on any storage device that can be formatted (meaning not optical), however, a few notes on that:

  1. Be ABSOLUTELY SURE which device you’re formatting before you commit to it.
  2. DO NOT use your computer while the format is taking place.
  3. If the device you’re formatting is over 4GB in size, I strongly recommend paying the measly $3.30 for the unlimited-speed version, else you’ll be waiting a long, long time for the format to complete.

Things this utility will not do

  1. It will not make a slow USB stick any faster concerning file transfers. If the device is slow because it’s old, well, there’s not really anything you can do about that.
  2. It probably won’t make a USB stick any more reliable than it was. If the stick had questionable stability beforehand, performing a low-level format doesn’t necessarily guarantee that it will fix that problem. Sometimes a USB stick that is too far gone simply can’t be repaired.
  3. It will not reassign drive letters. Even though this is true, the utility is well-designed, so when you launch it, there’s a nice little link that can take you directly to the Windows Disk Management Console where you can change things like that.

Should you always go with a low-level format when erasing a USB stick or hard drive?

Absolutely not.

A low-level format is specifically for the instances where you’re trying to get a storage device that’s unusable usable again.

You should only use a low-level format if the storage device will not work or has instability issues even after you’ve performed a high-level format.

What if I just want to erase the MBR on a USB stick I made bootable?

Again, this utility was written very smartly, because it does have that option. When you choose the LOW-LEVEL FORMAT tab, at bottom right is a checkbox specifically just for that function:

image

Where this is useful is if you write a Linux ISO to a USB stick that stuck a boot loader on it (such as with UNetbootin) and you want it gone. The quick-wipe which removes all partitions and the MBR (Master Boot Record) is just what you would want to get rid of that stuff on a USB stick.

On a final note, use this utility with caution. Remember, low-level formatting is a last option and never a first.

Here’s where you can get it: Download HDD LLF Low Level Format Tool

2 responses to How To Repair An Unreadable USB Stick

  1. Monte August 15th, 2011 at 2:21 pm

    Great find Rick!

    I have two old (pre 1999) drives a 256 MB and 16 MB in my desk that are ‘dead’ will give this a shot. I have an old laptop that I can use instead of my tower so it it take some time it won’t keep me from working.
    :)

        Reply

  2. Saverio August 15th, 2011 at 4:18 pm

    On Linux, a common method of LLF is to use the “dd” command. Example:
    dd if=/dev/zero of=/dev/sda
    CAUTION: it’s just an example. You should replace “sda” with the device that corresponds to your USB stick and make sure it’s the right one!
    The use of the command “dd” usually requires root (administrator) privileges. It can be destructive, so make sure you specify the correct device. If unsure, ask for help.

        Reply

Leave a Reply