I have a 4TB USB Hard drive that's plugged into the lightning port on my Mac Pro. It has always seen it as a USB device. Now it sees it as a hard drive like the Mac OS Hard drive that I am using for my Mac. I just want to know why it stopped seeing it as a USB Device and now sees it has a hard drive. I am asking because I am worried that it will see the other USB devices that I plug into it as hard drives. Can someone please tell me why this happened?
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MP All Models Mac sees USB as hard drive???
- Thread starter simalexander
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My mac is version 10.15.5. I just want to know why it changed from USB to a hard drive. I have 2 other USB Hard Drives plugged into my Mac Pro but the Mac sees them as USB devices. Why is it the one plugged into my lightning port that changed into a hard drive?
Im sure you meant thunderbolt. But Is it a USB or thunderbolt drive? The 2 are not the same. Im assuming, since i don't know what mac pro you have, that you're talking about thunderbolt over a USB type c plug? My guess is the controller on the harddrive has both thunderbolt and USB connections and the one time you plugged it in, it incorrectly synced up via the USB channels and then when synced up again via thunderbolt. Thunderbolt is a direct connection to the hardware busses, like a built in drive. I don't see a real issue here. The type of connection is based off the controllers on the disk drives.
So what mac do you have and what hard drive so we can get a bigger picture of what going on?
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I guarantee you there’s nothing wrong.
either way, disk utility decided to call it an external hard drive, which is what it is, this could've changed because of a firmware or software update you’ve done. This could also change if you recently changed your USB C/thunderbolt cable that connects the drive to the mac pro, if thats the case, then before you were using a USB C cable that was using the serial bus to connect to your mac as @lostless mentioned, and now it is seeing it as a thunderbolt device with the new cable. another possibility is that it didn't recognize thunderbolt compatibility until now. Regardless of the case I assure you there is nothing to be worried about and everything should be working as expected.
either way, disk utility decided to call it an external hard drive, which is what it is, this could've changed because of a firmware or software update you’ve done. This could also change if you recently changed your USB C/thunderbolt cable that connects the drive to the mac pro, if thats the case, then before you were using a USB C cable that was using the serial bus to connect to your mac as @lostless mentioned, and now it is seeing it as a thunderbolt device with the new cable. another possibility is that it didn't recognize thunderbolt compatibility until now. Regardless of the case I assure you there is nothing to be worried about and everything should be working as expected.