osx - Read Only USB Drive can't be erased/re-set

26
2014-06
  • Nate

    I bought a 32 GB flash drive several months ago, and after using it for a month or two, something happened to it. Right now, the drive has become read only.

    I tried using Mac OS X's Disk Utility, tried using the Windows Disk Management MMC snapin, and tried to erase it via the terminal on both OS X and Ubuntu. None of these worked to get it formatted so I could use it. They both keep saying that it wouldn't work, and couldn't be done because the drive was read only.

    Any other ways that I can try to erase and re-set my flash drive?

    • Answers
  • Sathya

    Maybe there is something such as a button on your flash body to make it Read-Only.

    enter image description here

    If no, Try the below steps in Windows :

    • Insert your USB (4GB+ preferable) stick to the system and backup all the data from the USB as we are going to format the USB to make it as bootable.
    • Open elevated Command Prompt. To do this, type in CMD in Start menu search field and hit Ctrl + Shift + Enter. Alternatively, navigate to Start → All programs → Accessories → right click on Command Prompt and select run as administrator.

    • When the Command Prompt opens, enter the following command:

      DISKPART  and hit enter.
LIST DISK and hit enter.

      Once you enter the LIST DISK command, it will show the disk number of your USB drive. my USB drive disk no is Disk 1.

    • In this step you need to enter all the below commands one by one and hit enter. As these commands are self explanatory, you can easily guess what these commands do.

      SELECT DISK 1 (Replace DISK 1 with your disk number)
CLEAN
CREATE PARTITION PRIMARY
SELECT PARTITION 1
ACTIVE
FORMAT FS=NTFS
ASSIGN
 EXIT

    For SanDisk flash memories,

    This is a known hardware error and can't be fixed. Sandisk is aware of the issue, although there is no official recall for the product. This is an offical answer if you contact customer service:

    I understand that you are getting write protection error while accessing your Cruzer flash drive. The flash drive has detected a potential fault and has become write protected to prevent data loss. There is no method to fix this. You will need to backup your data and replace the flash drive.

    Our team of developers is in combination with the OS developers looking into a solution to resolve this issue.

    Please note that only a minor percentage of users are experiencing the write protection issue and these are the customers posting on the internet to find a solution.

    Solution 1: Return to where you bought and get a refund (as others usb drives might have the same issue) Solution 2: Contact Sandisk customer service and get a refund, for the same reasons


    • Related Question

    osx - Emulate a USB port as a USB flash drive?
  • Wilco

    Does anyone know of any software that can emulate a USB flash drive through an available USB port in OS X? Perhaps some way to map a directory to a USB port that could then be connected to another device that supports reading USB storage devices?

    I'd love to connect my laptop to my car's USB port and access files as if it were a USB drive. I know about the target disk mode with firewire (not sure if this is also supported over USB), but I was hoping for something that doesn't require booting outside of the OS (I want to retain use of the machine).

    I'm thinking there may be hardware limitations that prevent software from doing this by itself.

    Any ideas?


    • Related Answers
  • Spiff

    Unfortunately, USB makes a firm distinction between the Host and the Device. If the USB receptacle on your car has the standard USB A (Host) connector like a PC would have, it means the car's computer wants to be the Host, just like your computer wants to be the Host, so they would most likely conflict with each other and not be able to talk to each other.

    Some people have made "USB file transfer cables" for connecting two Hosts together. These cables have an embedded chip that does the work of making the two Hosts appear as devices to each other. I believe these products assume both Hosts are full-fledged PCs, not embedded systems that happen to have a Host connector. I don't have experience with these cables, so I'm not sure whether a software install would be required on one or both ends. It might be worth looking into.

    The USB Implementers Forum (the body behind the USB spec) eventually realized the limitations of the Host vs. Device distinction, and created the USB On-The-Go (OTG) specification as a way for USB-capable things to switch between the Host and Device roles on the fly as needed, depending on what they're talking to. However, I think you'd probably need both ends to support USB OTG.