Step 1: Download the new firmware file from your local D-Link technical support site, or http://www.dlink.com. This file should be saved to the local storage of the computer you are using to perform the upgrade.
Step 2: Make sure your computer or mobile device is connected to the DIR-505 by Wi-Fi. Open your web browser and enter http://dlinkrouter or http://dlinkrouter.local into the address bar.
Step 3: At the login page, enter the Admin Password. If you have not changed the administrator password, leave the field blank. Click Log In.
Step 4: Move the cursor to the Maintenance tab at the top of the page and then click Firmware from the menu on the left-hand side.
Step 4: Under the Firmware Upgrade section, click the Choose File button. Locate the file you downloaded in Step 1 and select it as the file you wish to open. Then, click the Upload button to commence the firmware upgrade process. The upgrade may take up to 30 seconds to complete. Do not unplug the router at any time during the firmware upgrade process, as this can permanently damage the unit.