I want to delete my external 1TB USB Drive and format it with "Mac OS Extended (journaled)" and GUID Partition Scheme but the button for partitioning the drive is greyed out and non clickable. I can delete the Drive but the option to choose the Partition Scheme is not there and it automatically uses MBR.
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Can not format drive with GUID
- Thread starter meilon24
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Could you tell us who made the drive?
Does it have any "manufacturer proprietary software" on it that prevents it from being completely erased?
I'm thinking of possibly a "custom partition" that cannot be deleted with Disk Utility?
If so, you may need to go to the manufacturer's site and download their drive management software.
Sometimes, this can be used to remove the proprietary software and partition (if one is there).
Does it have any "manufacturer proprietary software" on it that prevents it from being completely erased?
I'm thinking of possibly a "custom partition" that cannot be deleted with Disk Utility?
If so, you may need to go to the manufacturer's site and download their drive management software.
Sometimes, this can be used to remove the proprietary software and partition (if one is there).