Mar 18, 2020 Here's how to open one of the multiple photo libraries that you might have on your Mac or on a connected external drive: Press and hold the Option key as you open the Photos app. Select the library that you want to open, then click Choose Library. Photos uses this library until you open a different one using the same steps. But if you want change your Mac computer to Windows PC, then you need to transfer you all data from Mac to Windows PC. The most important thing is your photos and videos. You can transfer all your photos from iPhoto to Windows with simple steps. To do so, open 'iPhoto' on your Mac and select all your photos to transfer. You can have multiple photo libraries in Photos app for Mac OS X. You can switch between libraries with simple steps. If you want to select a different library, then hold down the 'Option' key when you launch 'Photos' app ans select the photo library which you want to open.
You can have multiple photo libraries in Photos app for Mac OS X. You can switch between libraries with simple steps. If you want to select a different library, then hold down the 'Option' key when you launch 'Photos' app ans select the photo library which you want to open. If your library is stored on an external drive, then you need to connect that drive to be able to select and switch to that photo library in Photos app on Mac.
Open Photos Library Mac
Following are the steps to Switch Between Libraries in Photos App for OS X:

- Launch 'Photos' app on Mac OS X.
- Hold down 'Option' key on your keyboard.
- Double-click on 'Photos'.
- Choose the name of photo library that you want to open.
Change Photo Library On Mac
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