Problem
So you needed to enter Time Machine to retrieve a file or folder from a previous state, but all your restore points are greyed out or missing. You know you’ve been backing up daily and that you have plenty of space left for backups, so what gives?
Solution
In my case, it turned out to be very simple. All I had to do was reconnect to the hard drive that was hosting my Time Machine Backups – in this scenario; it was my Time Capsule. First, I make sure I’m on the same network as my Time Capsule and using Finder, I navigate to Time Capsule under Locations and click Connect As… Once connected, my restore points should all be visible again. If you’re using a hard drive instead of a Time Capsule, then it should be as simple as connecting your hard drive to your computer.
Why did my Time Machine Backups go missing in the first place?
I use a MacBook Pro, and use it both at the office and at home daily. My Time Capsule happens to be at home, and when I take my laptop to the office, I’m on a different network which “breaks” the link to my Time Machine Backups and therefore gives me greyed out restore points, placeholders if you will, instead. However, once I’m back home, I can connect to my Time Capsule and regain access to my Time Machine Backups, and the restore points become “white” instead of greyed out, meaning they are accessible.