I'm having trouble ejecting the external hard drive to which I moved my main Photos Library when I want to transport my MBP. is there any way to stop Photos.app from accessing the HD so I can eject it properly without having to restart the computer every time? Is there any risk of corrupting file by doing so?
Quite frankly, you can head the Activity Monitor to kill the Photos app and then it cannot access your external hard drive anymore.
Just launch Activity Monitor via Spotlight Search > find the running Photos app > double-click the Photos app > click Quit in the new window.
With no accessing from the Photos app, drag the external hard drive icon to Mac Trash and then you can remove it from your MacBook Pro. The files on the drive will not be corrupted if you eject th drive properly.
Take care~
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