Local LAN, just connecting to my wireless router on which the DLink is as well.
iOS 9.0.2 (13A452)
iPhone 6
I've tried to correlate firmware upgrades both on the iOS side and the DLink side and haven't found one that's firm enough to be the culprit. It will just wait and wait to connect, then that strange error crops up. ... and that's all things being equal and unchanged. Strange, strange, strange.