Can't partition an External Hard drive on High Sierra

The option to partition my 1TB Seagate hard drive is greyed out. Please help

MacBook Pro 13", macOS 10.13

Posted on May 3, 2019 3:03 AM

Top-ranking reply

Luis Sequeira1

Level 9

73,032 points

Posted on May 3, 2019 3:11 AM

Do View->Show All Devices.

Then select the full disk instead of the volume, and try the partitioning.

View in context

Similar questions

Partitioning my External Hard Drive I want to partition my External Hard Drive. I have erased and Formatted it to Mac OS Extended (journaled) and the partition option in Disk Utility is still greyed out. I have run Terminal command: diskutil erasedisk hfs+ External GPT /dev/disk2 but I get this message: Error: -69877: Couldn't open device Can anyone help? Thank you!
1429 5
How to partition external hard drive? Partition option greyed out I'm trying to partition my Seagate 2TB external hard drive with my MacBook Air M1. I've formatted it to Mac OS Extended (Journaled) and ExFAT but neither solves the issue. I've attached two screenshots which show I also don't get the option to add a 'Scheme' e.g. GUID partition map.
1156 1
Unable to partition external hard drive on Mac using Mojave I have erased and reformatted several times, but partition in Disk Utilities continues to be greyed out. I have even tried different Macs with Mojave. I have other external drives partitioned, and First Aid doesn't show anything wrong with the external drive. I am really at a loss.
1018 5

3 replies

Top-ranking reply

Luis Sequeira1

Level 9

73,032 points

May 3, 2019 3:11 AM in response to dombel

Do View->Show All Devices.

Then select the full disk instead of the volume, and try the partitioning.

dialabrain

Level 10

135,527 points

May 3, 2019 4:43 AM in response to dombel

You need to reformat the top level of the drive replacing "Master Boot Record" with GUID.

dombel Author

Level 1

8 points

May 3, 2019 4:39 AM in response to Luis Sequeira1

Unfortunately, the button is still greyed out. Any other tips?

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Can't partition an External Hard drive on High Sierra