Occasionally after restarting my MacBook Pro the Spotlight search feature will stop working. After several reboot attempts, the search feature will still not work!
The trick I found to fix this issue is to rebuild the Mac Spotlight search index. There are several ways to do this but the way I prefer is to use the Terminal.
In the terminal, type in this command:
sudo mdutil -E /
You will be prompted to enter your password. Once that’s completed, you should see something like this:
$ sudo mdutil -E /
Password:
/:
Indexing enabled.
mdutil is the service that manages metadata used by Spotlight. E erases and rebuilds the index in the specified volume, which is / in this case.
Indexing may take some time, but in my experience the Spotlight search usually starts working again after just a couple of seconds.