I'm running Lightroom 5.7.1 on a MacBook Pro running OS X Yosemite 10.10.3. My hard drive capacity is 500Gb. I recently switched to Lightroom from Aperture and before migrating my whole library I tried Lightroom with only my new photos for a few months. In Lightroom, it says that my MacBook hard drive has 49Gb of free space. I moved my Aperture library to an external hard drive (and deleted the local copy) to create room for the the import of files from Aperture. Finder now says I have 334GB free on my hard drive but Lightroom still thinks I only have 49Gb free. As a result, it won't let me run the import from Aperture plug-in. I have restarted my computer, cleared the Lightroom cache, emptied the Finder trash, and it's not worked.