Cannot partion drive, Mac El Capitan, option greyed out

Help !

Purchased a new WD drive on the weekend with the intention of using it as a time machine & general drive. I was able to connect the drive & reformat to Mac HFS with extended journaling. However, when I try to select the create partition option in disk utility the option is greyed out & cannot be selected.
The drive can be used & accessed & even works as a time machine backup, however a partition cannot be created. I have re-formatted a few times & even formated back to windows format & back to mac.

Looking at diskutil it appears that the issue is the drive is stuck as an “FDisk_partition_scheme” not GUID as required for El Capitan to partiion the drive.

Does anyone know how to fix this & change the partition scheme on the drive ?

dev/disk1 (external, physical):
0: FDisk_partition_scheme *4.0 TB disk1
1: Apple_HFS External HD 4.0 TB disk1s

Thanks !

Are you unable to click the Options button in the partition tab in order to change it to GUID Partition Table?

Thanks for the reply
The actual partition tab is greyed out & does not allow me to access the partion tab at all.

Which external hard drive do you have? Is it a RAID unit?

No basic WD Elements 4tb

Found the solution on the apple support site
from terminal
diskutil erasedisk hfs+ External GPT /dev/[diskname]

[diskname] is the higher level disk in disk utility, (the one with the manufacturers name)

After running this and going back into disk utility I was able to access the partion button after enabling journaling from the file menu

Hi bmac!

I have the same problem but when I go into terminal and enter “diskutil erasedisk hfs+ External GPT /dev/[diskname]” - my diskname being WD Passport … it still doesnt work.

Any suggestions would be most welcome. I have been struggling for 4 hours and I fear I may not have a macbook to work on soon due to its accidental fall out the window…

Thank you in advance

Hi Margaret,
Sorry i don’t have any other suggestions, i think i lucked out by trying out this solution i found on applesupport

Good luck !

Thank you bmac, worked like a charm!