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humpbacktwale

macrumors regular
Original poster
Dec 20, 2019
204
33
I used a 3 pass erase on a usb drive, and in the result of the erase, it states:

"
Mounting disk
Could not mount disk4s1 after erase
Invalid disk.

Operation failed…
"

Now the usb drive seems to be empty, so am I to assume the erase as in fact successful given the "after erase" part? If so, why was it unable to mount it after? Unplugging it and plugging it back in seemed to have mounted it correctly, so I was unsure why it wouldn't work the first time.
 
Try RE-erasing it.
This time, don't use "secure erase" at all.
See if that works.
 
Before trying that, could I ask whether or not the dialog it displayed means it wasn't able to complete the secure erase, or whether that just means that after it was done, there was an issue with the automatice remount? I can live with the latter as it worked fine after I took it out and put it back in.
 
"could I ask whether or not the dialog it displayed means it wasn't able to complete the secure erase, or whether that just means that after it was done, there was an issue with the automatice remount?"

I have no idea.

Why don't you just try a simple erase (without any "zeroing out") one more time?
 
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