why my external HD can not be mounted or viewd by a Macbook

Question

Level 1

4 points

why my external HD can not be mounted or viewd by a Macbook

Hello

I can not see my exertenal HD from finder.

I do have G-Technology HD and I use it with TimeMachine. Thta HD has two partition.

The first is use to backup with TimeMachine, a macbook air and the second partition is used to backup a macbook pro with timemachine.

It worked fine until I look into the External HD (macbook partition). Now it's not possible to mount the External HD. From Finder, I can not see eighter the first partition or the second.

I plugged it to another mAcbook air and no way to see inside the External HD.

Howerver, I pluggged it into a ubuntu 14.04, and I could navigate throught the External HD

Why I can see the content of the External HD with an ubuntu nad not with a Macbook??

And how can I solve that problem?

Cheers

Pierre

iMac - MacBook Pro - MacPro, Mac OS X (10.6.3)

Posted on Sep 15, 2016 7:41 AM

Reply

Answer 1

Sep 15, 2016 2:54 PM in response to pierrot10

El Capitan has permissions setup a lot tighter than earlier versions of OS X and it can become problematic to open files from a different computer. You need to tell us what OS you are running on all the computers.

I suspect Ubuntu is having no problem because it is not working under the same permissions restraint.

It worked fine until I look into the External HD (macbook partition).

Whatever you did here caused permissions change.

Remember that plugging a drive directly into a computer and using it plugged into an Airport will have different permissions problems.

I don't have much in the way of a solution. Apple changed the repair permissions on El Capitan.

Do you have a Mac running older version of OS X?

If both your partitions are used just to do Time Machine backups..

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Answer 2

pierrot10 Author

Level 1

4 points

Sep 15, 2016 3:00 PM in response to LaPastenague

Dear Sir,

Thank for your reply.

I do have El Capitain.

So how can I restaure my External HD to make it working again with Time Machine?

and how can I "manually" take a folder from HD with Finder?

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Answer 3

Sep 15, 2016 3:46 PM in response to pierrot10

My recommendation is to buy a second USB drive.. do not swap the drives between computers.. keep one drive for one computer and the other drive for the other one.

It also means you will need to reformat the USB drive to make it accessible.. but try and repair permissions first.

You can still repair permissions from the command line.

http://lifehacker.com/verify-and-repair-permissions-from-the-command-line-in-174 1718667

Once you repair permissions you should be able to access your folders.

But please do not swap disks around on El Capitan.

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