Longtime troller, first time poster. I have a 64GB Corsair UFD thumb drive that I cannot use. I don't even care about what is/was on the disk, I just would like it to be available. While the disk itself shows up in Disk Utility, it can only be Verified (all other options are greyed out). The single partition is JHFS+ (which, I gather, stands for Mac OS Extended (Journaled)) but will not mount. Disk Utility recommends I run First Aid on it, but again Verify Disk is the only option available. When I run Drive Genius 3.2, the volume shows up but cannot be affected. Mousing over the volume pops up a message that says "The current operatio canot be performed on this drive. The drive is locked (read-only). If this is not an optical drive, please unlock the drive to work with it." As I cannot mount the drive to unlock it or change its permissions, I even fooled around with Terminal a bit, following internet threads with somewhat similar problems. diskutil list identified the trouble disk as follows: /dev/disk2 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *63.1 GB disk2 1: EFI 209.7 MB disk2s1 2: Apple_HFS Lion Survivor 62.7 GB disk2s2 And diskutil info /dev/disk2s2 provided this information: Device Identifier: disk2s2 Device Node: /dev/disk2s2 Part of Whole: disk2 Device / Media Name: Drive Genius Volume Name: Lion Survivor Escaped with Unicode: Lion%FF%FE%20%00Survivor Mounted: No File System Personality: Journaled HFS+ Type (Bundle): hfs Name (User Visible): Mac OS Extended (Journaled) Journal: Unknown (not mounted) Owners: Disabled Partition Type: Apple_HFS OS Can Be Installed: No Media Type: Generic Protocol: USB SMART Status: Not Supported Volume UUID: EF8BF6C2-5899-34ED-BEE2-BFF04F479784 Total Size: 62.7 GB (62738358272 Bytes) (exactly 122535856 512-Byte-Blocks) Volume Free Space: 0 B (0 Bytes) (exactly 0 512-Byte-Blocks) Device Block Size: 512 Bytes Read-Only Media: Yes Read-Only Volume: Not applicable (not mounted) Ejectable: Yes Whole: No Internal: No I tried various approaches to access or erase the disk, to no avail. I am fairly new to command-line work so I probably didn't get some of the various command options right. Examples of things I tried: $ sudo diskutil eraseVolume JHFS+ UntitledUFS disk2s2 Started erase on disk2s2 Lion Survivor Unmounting disk Erasing newfs_hfs: cannot create filesystem on /dev/rdisk2s2: Permission denied Mounting disk Could not mount disk2s2 with name Lion Survivor after erase Error: -69832: File system formatter failed $ sudo diskutil eraseDisk JHFS+ Jimmy disk2 Started erase on disk2 Unmounting disk Error: -69877: Couldn't open device $sudo dd if=/dev/zero of=/dev/disk2s2 dd: /dev/disk2s2: Permission denied So, anyone have any thoughts? Thanks.