Photos library won’t load? Time to rebuild it. Here’s how

Have a Photos library on your Mac that is missing previews, won’t open images or videos, or displays a never-changing message that it’s loading favorites or uploading images to iCloud Photos? Try rebuilding the Photos library:. Quit Photos.

Hold down the Command and Option keys while launching Photos. When prompted, click Repair.

Click Repair and be prepared to wait.
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