external hard drive problem with el capitan

Question

external hard drive problem with el capitan

I have 2 external hard drives which I back up time machine to regularly. They are both freedom hard drives. One of them works fine, but the other one is causing a problem. When I plug it into the USB port, it shows in the finder for a couple of seconds, and then disappears and I get a message saying the disk was not ejected properly. I also have an old macbook air, and there is no problem with that. I have run first aid, on the external hard drive, and even reformatted the drive (on the macbook Air) but the problem is still the same. The external hard drive works fine on the macbook air, but the problem persists on the new macbook pro.

I have El Capitan on both MacBooks, but 10.11 on the macbook air, and 10.11.1 on the macbook pro, so I am guessing that there is a big in 10.11.1

Can anyone back this theory up by any chance? Or has anyone experienced a similar problem?

Mac Pro, OS X Yosemite (10.10)

Posted on Dec 1, 2015 11:46 PM

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Answer 1

OGELTHORPE

Level 9

57,305 points

Dec 2, 2015 3:31 AM in response to Flashymcbashee

I would test the problematic HDD with different USB cables and if necessary, take out the bare drive from the enclosure and install it in a known functional enclosure.

Ciao.

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Answer 2

Dec 2, 2015 11:50 AM in response to OGELTHORPE

Thanks for responding, but I have no idea what you mean. As I use the same USB cable for both computers, presumably it is not that which is at fault, becausee the HD works on one computer but not the other. I don't know what you mean by this though

OGELTHORPE wrote:

I would test the problematic HDD with different USB cables and if necessary, take out the bare drive from the enclosure and install it in a known functional enclosure.

Ciao.

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Answer 3

OGELTHORPE

Level 9

57,305 points

Dec 2, 2015 1:06 PM in response to Flashymcbashee

I am suggesting that the enclosure in which the HDD resides may have faulty circuitry or compatibility issues with the MBP. Install it in another enclosure and see if there is a difference. All USB ports are not necessarily the same so you should also try them all.

Ciao.

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Answer 4

Dec 2, 2015 1:15 PM in response to OGELTHORPE

Thanks but I don't know what you mean by an enclosure. I have a hard drive 1 unit - 1 piece, and the cable with connects it. I've tried it in both USB ports on the macbook

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Answer 5

OGELTHORPE

Level 9

57,305 points

Dec 2, 2015 1:38 PM in response to Flashymcbashee

Both of the HDDs that you mention in your original post are installed in an enclosure. If you open it up, you will find the bare drive that is plugged in to a SATA connector. Note this picture:

The bare HDD is on the left connected to the SATA circuit which has the USB cable connected. The balance of the enclosure is on the right.

Ciao.

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Answer 6

Dec 2, 2015 2:18 PM in response to OGELTHORPE

I can't do that because the whole HD has a protective rubber outer, which can't be removed. I just don't think it's anything to do with the HD, but something to do wit the upgrade to 10.11.1. Otherwise why does it behave fine when plugged into a macbook with 0.11, and only misbehave when plugged into 10.11.1? And why did it behave fine before I upgraded the macbook pro to 10.11.1?

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Answer 7

OGELTHORPE

Level 9

57,305 points

Dec 2, 2015 3:27 PM in response to Flashymcbashee

Perhaps you are correct, but then why one external HDD is having problems and not both? Though computer hardware is usually fairly stable, it is not always so, posts on these forums being evidence of that phenomena.

Ciao.

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