Mac Pro 2013 shows no entry sign when starting up from external boot drive

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peacebruvva Author

Level 1

6 points

Mac Pro 2013 shows no entry sign when starting up from external boot drive

Hi,

Upgraded from 2012 Macmini to 2013 Mac Pro binstyle.

System was stable with Yosemite so superdupered to a Samsung 850 ssd and cloned to MacPro 1tb internal ssd.

This worked fine.

Next I upgraded Macmini to el Capitan to test how it goes with all my music production software since some don't play nice with Capitan.

So far so good so I cloned Macmini to another ssd, same Owc enclosure with the intention of running it externally from Mac Pro for further tests.

This is where it goes wrong.

On choosing startup disk from Yosemite, the external Capitan drive starts ok but stops bar half loaded showing a no entry sign.

The Samsung ssd was guid formatted.

The drive enclosure worked for Yosemite clone.

Is there something I missed or don't know about?

Cheers

Posted on Jan 4, 2016 5:23 AM

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Answer 1

lllaass

Level 10

210,519 points

Jan 4, 2016 6:10 AM in response to peacebruvva

Prohibitory symbol

When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from.

If you're using your Mac at a school or business, it might be trying to start from the wrong version of OS X. Contact your IT department for more help.

If this is your personal Mac, try reinstalling OS X by using OS X Recovery.

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Answer 2

peacebruvva Author

Level 1

6 points

Jan 4, 2016 7:28 AM in response to lllaass

Thanks for getting back lllaass!

Yes its a personal Mac.

The external drive boots fine from Macmini 2012 which makes me assume the files are all in order.

But when plugged in to and started up from Mac Pro 2013, the no entry symbol appears.

So are you suggesting that I reinstall osx onto the Mac Pro via recovery?

This is not what I want since a stable working Yosemite is on the main drive, I want to boot from the external Capitan drive so I can do further tests.

Am I clear or still not getting it?

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Answer 3

lllaass

Level 10

210,519 points

Jan 4, 2016 7:40 AM in response to peacebruvva

- have you tried booting normally on the Mac Pro and going to Disk Utility and repairing the problem external disk?

- So the external problem disk has El Capitan. There appears to be something wrong/missing from that disk when booting on the Mac Pro, When you cloned it did you also clone the Recovery partition? If so can you boot to that El Capitan Recovery partition?

----- If so then boot from that reinstall EC on top of the existing EC installation.

----- If not then from Yosemite download the EC installer and click on it and install EC over the existing EC installation on the external disk

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Answer 4

peacebruvva Author

Level 1

6 points

Jan 12, 2016 5:54 AM in response to lllaass

Hi lllaass,

Thanks for reply! Sorry for late response, got busy with another project.

I didn't use disk utility to repair problem with the external disk as that was my only working EC os as the macmini internal drive stopped working and wanted to clone it beforehand.

But I will give that a go at weekend and let you know how it goes. Your response is well appreciated .. Thanks!

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