DISKPART: "DiskPart has encountered an error: The media is write protected."

I got this error from DiskPart when I entered the command "create partition primary".
The disk was set to read-only. To find out if the disk is read-only or not is to issue a command "detail disk". Look for Read-only : yes.
To clear the read-only, issue a command "attributes disk clear readonly"
You should be able to create a partition