5TB drive disconnects suddenly and doesn't appear in Finder for a few hours on the new M4 Max
I have a 5TB Seagate external HDD that was working perfectly on my Intel-based MacBook for over a year. Recently, I got a new MacBook Pro with the M4 Max chip, and initially, the HDD worked fine for a few hours. However, it suddenly got disconnected and stopped appearing in Finder. Interestingly, it still shows up in System Information under USB.
When I connected the HDD back to my old MacBook, it didn’t show up there either. But after about an hour, it reappeared on both laptops. This cycle keeps repeating — the drive disappears for an hour and then comes back again. I tested it on a Windows laptop, and it works perfectly there.
When the HDD is connected but not visible in Finder, Disk Utility keeps loading. Once it appears in Finder, Disk Utility also works normally. I even ran First Aid, and it completed successfully, but the issue persists.
I tried using a different cable, but the problem remained the same. I can feel the hard drive spinning when I touch it, so it is getting power.
I also have two other external HDDs — a 5TB and a 10TB (with external power) — and they work fine all the time.
In System Information, when the problematic HDD is detected in Finder, the 'Free' and 'Writable' fields are displayed. However, when the drive disappears, these fields are missing. I reached out to Seagate support, but they couldn’t provide a solution.
I’m trying to understand whether this is an issue with the HDD itself or a settings/configuration problem on the MacBook. Any help would be greatly appreciated.
MacBook Pro 16″, macOS 15.4
