Hello, I am running a Macbook Pro 15" under El Capitan 10.11.3. For the past few weeks, whenever, I am trying to use one of the components of the Share menu or button (email this page, airdrop, messages, etc), it never works and most of the menu actions in the Finder or Safari are becoming greyed and unusable ??? I have been googling for solution, but to no avail. Before I decide to reinstall the OSX, could anyone suggest less drastic solution. Thanks R.