I had a NAS on my network at one time but sold it, but OS X still attempts to mount it every time that I restart my iMac, and complains via a pop-up that it is not available. I do not see it listed as an auto-mount under my login settings, so I don't know how to remove it or where the information to auto-mount is coming from. It gets annoying to have to cancel the pop-up upon every boot.