I've had trouble with file sharing since I started using Mavericks when it came out. I have two Macs. An iMac which has an external drive connected to it, and a Macbook Retina. I use the iMac to store everything including pictures, iTunes, and files. When I do a clean reboot of the Macbook, it sees the iMac and shows all the shared stuff. After a while (especially after sleeping), the finder window on the Macbook with shows "Connection Failed" or an empty window when I click on the iMac. I can still get screen sharing to work, but that is it. AFP and SMB are checked on for both machines. Bizarre since it works some of the time. No other issues on my network. Problem occurs with wired or wireless connections. Thanks in advance.