If you are having issues connecting to your D-link wireless network with an Apple iPhone, iPad, MacBook or iMac; D-Link’s ‘Smart Connect’ might be the cause. This applies to Dual band routers, ie: Models DIR-8xx. Disabling Smart Connect and naming your networks differently will generally resolve this problem.
How to Fix
Connect any device to the router with Ethernet, or use a non-apple device connected wirelessly.
Browse to your Router’s settings page (usually http://192.168.0.1 or http://dlinkrouter.local)
Go to Settings > Wireless
Turn off Smart Connect
Name your networks differently (ie: Add 2G to the end of your 2.4Ghz network)
Save Settings and reconnect