Yes,
I had done that exactly but I get this message
"Photos does not have the necessary permissions to create a Photos library
in the folder that contains your library."
I am not using iCloud Photo Library.

Cheers
Rosemary

Rosemary Spark
PO Box 781
South Fremantle WA 6162 Australia
Phone: + 61 8 94336609
Mobile: 0414268043
arkaysp...@gmail.com

On 8 May 2015 at 12:02, Ronni Brown <ro...@mac.com> wrote:

> Hello Rosemary,
>
> You don't mention if you are using *iCloud Photo Library*?
>
> You can still use Photos for OS X, and keep local copies of all your
> original pictures and videos, with an external hard drive.
>
> *How to use Photos for OS X with an external hard drive:*
>
> Like iPhoto, your Photos for OS X library can run off an external hard
> drive.
> Here's what you need to do.
>
>
>    1. Make sure you've *quit Photos for OS X.*
>    2. *Move your existing Photos library* from your user folder's
>    Pictures section to an external drive.
>    3. *Option-click Photos to launch it*, and select your Photos library
>    from the external drive.
>
>
> If you're syncing to iCloud Photo Library
> <http://www.imore.com/icloud-photo-library>, it's worth noting that
> you'll have to have your drive plugged in to sync or view your library; you
> can't create a second Photos Library that has iCloud Photo Library enabled
> on your Mac.
>
> Cheers,
> Ronni
>
> *13-inch MacBook Air (April 2014)*
> 1.7GHz Dual-Core Intel Core i7, Turbo Boost to 3.3GHz
> 8GB 1600MHz LPDDR3 SDRAM
> 512GB PCIe-based Flash Storage
>
> OS X Yosemite 10.10.2
>
> On 8 May 2015, at 11:27 am, Rosemary Spark <arkaysp...@gmail.com> wrote:
>
> My photo libraries are on an external drive. When I attempted to open with
> the new Photos app  (using Option key) it starts then comes up with a
> message
> "Photos was unable to make a copy of your library before preparing it.
> Photos does not have the necessary permissions..."
>
> The Apple support article https://support.apple.com/en-au/HT204484
> <https://support.apple.com/en-au/HT204484>only mentions (twice!) how to
> fix this via Terminal commands if your library is in the Pictures folder on
> your hard drive.
>
> Anybody any ideas?
>
> Macbook Pro Retina 15-inch, Early 2013
> Yosemite 10.10.3
>
> Rosemary Spark
> PO Box 781
> South Fremantle WA 6162 Australia
> Phone: + 61 8 94336609
> Mobile: 0414268043
> arkaysp...@gmail.com
>
>
>
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