External HD keeps closing when importing from After Effects

I am running AE CS6 v11.0.3.6 running on Mac OSX v10.9. I have most of my files on a 3TB Seagate Backup Plus Drive. Never ran into an issue before. But now when I attempt to open the HD from within AE to open a file or import an image, the external HD window remains open for a few seconds - then abruptly closes. I am unable to search the drive for the file I want or import anything.

Any clues as to why this would be happening? I just checked for AE updates and looks like I'm updated to the latest version. I also restarted the system and am still having the same issue.