How do I get a lone missing app to appear in Spotlight searches?

When I enter a string that matches part of the name of an application on Mac, the OS X Spotlight search feature will suggest apps for me to launch. This works for every app except one: Mathematica:

While the string is recognized (presumably from my history) the application is not suggested, and the only way to launch it is directly from the Finder or some other awkward workaround.

Why would — indeed how could — a single lone application behave differently in this regard? How can an application hide itself in this way from Spotlight?

And most importantly: what can I do to restore this standard piece of functionality?

Note that this problem is unique to Mathematica. For example for JetBrains apps, I get:

Moreover, it extends to the Finder itself. For example if I search there I get

even though Mathematica is clearly there

I can reproduce this (for Mathematica only) by simply updating (download, open the DMG, drag the new version to the Applications folder, replace). This is indeed unique to Mathematica (in my experience). I update at least one app a day in this or similar ways, and none of them vanish as a result from Spotlight; only Mathematica.

Solution 1:

While this does not directly answer as to why that particular app does not appear in Spotlight, nonetheless as a workaround, try the following:

Explicitly exclude the App, via drag and drop from Finder, into System Preferences > Spotlight > Privacy, and then close/reopen Spotlight preferences and remove the App by selecting it, then click the minus button [-] at the bottom left of the list window.

The App should now appear in Spotlight, however it may disappear again if the root cause is triggered again.

Solution 2:

I was facing the same issue with Todoist and Microsoft Outlook. The answer above didn't solve the problem for me on MacOS Sierra 10.12.6, as you can only exclude whole folders now in the Spotlight Privacy tab. I tried that, but it didn't help. However a similar solution worked for me:

1. System Preferences > Spotlight > Search Results
2. Untick 'Applications'
3. Close the settings
4. System Preferences > Spotlight > Search Results
5. Tick 'Applications'

Solution 3:

For me the answer was, in the same fashion as the accepted answer, to exclude the entire harddrive and then re-eanble it.

As described here: https://discussions.apple.com/thread/7356551

Note: this is also the method recommended by Apple for rebuilding the Spotlight index, see support article here: https://support.apple.com/en-us/HT201716