# Solved: Unable to write to the last block of the device



## MPeg3

I have an 80 GB iomega external HD that I have been using on my PC. I want to format it to use on my husbands Mac. I tried Verifying the disk, Repair the disk and Erase the disk and all of them give me the "Unable to write to the last block of the device." error message.

Is there anything I can do to fix this?

Thanks
Peg


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## kanaitpro

try using diskpart, provided that you are on a windows machine. just make sure that you choose the right drive. if it less than 16 gb or so it has them in mb, but for larger drives, it calls them gb. see attached picture for reference. open an admin command prompt and type diskpart, then hit enter. the rest of it is on the picture. this works sometimes when other things don't.


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## MPeg3

Thanks so much. This worked for me. I still can't get my iMac to format it to be used with OS X, but it can at least be used for my Windows 7 laptop, so not totally a bust.

Again, thank you
PegM


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## kanaitpro

if you want the mac to use it, you can use a live dvd of a linux distro, like mint or ubuntu, and use gparted to make it hfs file system (i think that is what a mac uses) and that should work. but if i recall, mac will use the ntfs, at least the macs that i have here will read the flash drives i use with windows. anyway, glad it is at least half working.


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