extlib directory of the <install-dir> folder, right-click on your Java project and select Run As > Maven install.
Eclipse might need to be launched with Administrator privileges (right-click on eclipse.exe and run as Administrator).
To install the Custom action in NeoLoad, you need to copy your Custom Action:
lib/extlib directory of the NeoLoad project if the project is collaborativeextlib directory of your <install-dir> folder if the Custom action will be used in several projectsextlib directory of the <install-dir> folder, right-click on your Java project and select Run As > Maven install.