Hello. We have a NAS device (LenovoEMC px4-400r) located on the same subnet as a few MAC users (iMAC Yosemite). Log on credentials are managed directly from the NAS device, no domain integration. iMACS are hard wired, gigabit connectivity. They are connecting to the shared folders with the AFP protocol. Often times when viewing the folder contents, some files and/or folders appear to simply disappear. Remounting the folder seems to correct the problem temporarily. We do not have any issues at all with Windows machines. Are there any settings on the MAC that may affect how the machine views shared folders? I am not a MAC guy, decades of tcpip networking and it management experience though. Thanks.