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Example: If your device only supports 802.11b or 802.11g and it can’t connect to the router then you can try to change the 802.11 mode to solve the problem. If your devices all use the same 802.11 standard, you can set an ‘only’ mode to improve performance.
Step 1: Open an Internet browser (such as Internet Explorer) and enter http://dlinkrouter.local or http://192.168.0.1 into the address bar. Press Enter.
Step 2: Enter the password for your Admin account in the field provided. If you have not changed this password from the default, leave the field blank. Click Log In.
Step 3: Move the cursor to the Settings tab and then click Wireless from the drop-down menu.
Step 4: Click Advanced Settings… for the wireless band that you wish to change the wireless mode for. Choose your desired 802.11 Mode from the drop-down menu. The mode selection process is the same for the 2.4 GHz and 5 GHz bands, however the options available for each band are different.
2.4 GHz Band:
5 GHz Band:
Step 5: Click Save Settings to save your current configuration.