Sometimes, FARR just refuses to call the plugin on execution.
For example, I invoke the Network Connections Plugin and get a list of available network connections. Now when I try to execute one of the connections I get an error message saying something like: Windows cannot find "No help available.". Make sure you typed the name correctly and try again.
I am pretty sure that FARR is just trying to execute the path value of the result on its own, as status bar displays path of the selected result item and it says "No help available.", instead of triggering the plugin to execute the result.
I don't know what is causing that behavior but when FARR once enters that state none of the plugins that supply non-executable results work. And nothing helps, save FARR restart.