Why is my Seagate external HDD not mounting after Sequoia update?

System updated to Sequoia 15.6; Seagate external HDD connected and running but not mounting on M3 desktop. I have configured three volumes on my desktop and three volumes on my external HDD. I want them backed up externally but they no appear on DU


And DUs I use no longer appear on the side bar and I'm unable to add them because the side bar option is grayed out.

iMac 24″

Posted on Aug 15, 2025 08:26 AM

Reply
3 replies

Aug 15, 2025 04:38 PM in response to D.I. Johnson

Thank you for the information. Unfortunately, I have the M3 so I still can't. I'm not at all pleased that Apple diddles and changes things randomly. I should be responsible for my own security re: what I use to boot my own desktop from. My decision. If I screw up? That's on me. This is my computer. I don't need 'Big Brother' deciding such an internal issue for me. External security matters? Outside vulnerabilities? Absolutely. This? No.

Why is my Seagate external HDD not mounting after Sequoia update?

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