Finder doesn't show "Open With" menu, just "Fetching..." When I rightclick a file in Finder and hover over "Open With" (e.g. I have .mp3 files associated with VLC but sometimes want to open them with Audacity or iTunes, and then use "Open With"; or want to use LibreOffice for a spreadsheet file instead of Numbers), the "Open With" menu doesn't open and just shows, greyed-out: "Fetching..." and the menu with different apps doesn't appear, even when I wait for minutes. How can this be fixed?

P.S. I searched for previous posts about this problem and could only find &quot;Fetching...&quot; Behavior in Finder &quot;Open With&quot; Menu in Yosemite but that is more about Finder taking a few seconds delay for the pop-up menu to appear, while mine doesn't appear at all.
It might be time to rebuild your LaunchServices database.
You will need to reset any custom associations.

The simplest method to do this is using Onyx (freeware).

Maintenance tab/Rebuilding