Erase encrypted external drive

[Siron]

I have a Toshiba 1TB external drive that I encrypted. When I plug it in, it asks for the password but it won't accept it and I know it's the correct one as I've been accessing it. I don't care about losing the data so I want to erase it but DiskUtility won't let me - can't mount it, erase it nothing

I even tried it in Terminal with diskutil cs delete
3BDD1407-8142-4CA8-87E8-86E131162F8F

I get this message:

Started CoreStorage operation

Ejecting Logical Volumes

Destroying Logical Volume Group

Error: -69783: Unable to delete the CoreStorage Logical Volume Group

Can anyone please help?
Thanks
Alan

 

[Weaselboy]

Even though the volume is not mounted, can you see the drive it self above that like in my screenshot? You should be able to select that then in the erase tab reformat the entire disk.

 

[Siron]

I can see the volume but it's grayed out. I can select it and hit the Erase button and the Erase functions gray out and I get an error message
Alan

 

[Weaselboy]

Try this in Terminal.

diskutil cs delete /Volumes/TOSHIBA\ EXT

 

[Siron]

Okay here's the result

diskutil cs delete /volumes/TOSHIBA\ EXT

/volumes/TOSHIBA EXT does not appear to be a valid Core Storage Logical Volume Group UUID or name

Removed the \

NAME's-Air:~ NAME$ diskutil cs delete /volumes/TOSHIBA EXT

Usage: diskutil coreStorage delete lvgUUID|lvgName

Delete a CoreStorage logical volume group. All logical volumes will be removed.

Ownership of the affected disks is required.

It's still grayed out in Disk Utility.

Thanks
Alan

 

[UL2RA]

Have you tried selecting the main partition and not the sub-partition?
[doublepost=1497555905][/doublepost]Also, you can try a third-party partition app like this: https://www.paragon-software.com/home/hdm-mac/

The trial should work fine.

 

[Siron]

Have you tried selecting the main partition and not the sub-partition?
[doublepost=1497555905][/doublepost]Also, you can try a third-party partition app like this: https://www.paragon-software.com/home/hdm-mac/

The trial should work fine.

I cannot do anything with the main drive - only the partition. I'll try that software. I'm still baffled as to why it won't accept a valid password that I used three times before.
Alan

Edit: Don't see a trial version on that webpage

Edit: Found the MacWipe for free.

 

[UL2RA]

That's really bizarre.

 

[Siron]

It seems I have to create a bootable USB drive to allow the disc wipe to work. How about booting to disk utility and doing it from there?
Alan

 

[UL2RA]

Sorry about that ... that app absolutely does not do what I thought it did. You can try booting into recovery mode and using Disk Utility there. Or you can try the USB thing, but I'm not sure what the trial allows.

 

[Siron]

For some reason the link sent me to their main page. I found the link to the free trial of Hard Disc Manager. I'll try if today. I hope it will let me erase free space on my MacBook Air's hard drive as the Mac utility said I don't have enough free space to create a temporary file, yet it creates one and appears to be erasing free space for ten minutes until it finishes and says it cannot create a temp file - strange as you would have thought I'd get that message to start with.
Alan