SOLVED : Apple iMac NOT connecting to 5GHz WiFi


If you own a apple computer a iMac/Macbook or Macpro , then you probabely would have encountered this error. Your home wi-Fi router has dual channels a 2.4GHz & a faster 5 GHz channel. Now in my case my iMac late 2012 was not able to connect to my ASUS gigabit router which is dual channel.

I tried the following, all in vain

  • RESET the ASUS router to default settings
  • Clean install my iMac with latest OS Catalina

Still my router’s 5GHz network would show up in the ‘Network List’ but when connecting with corect password throws an error ” CANNOT BE CONNECTED TO NETWORK’


Check if your mac’s internal WiFi hardware support Dual Band !

5 GHz Network Band Capability Check on a Mac


1. Click the Apple icon located in the top-left portion of the screen and select About this Mac.


2. Click System Report on the menu displayed.



3. On the Left-hand side column, scroll down options until you see Network, then select the Wi-Fi option underneath it. Look for the “Supported PHY Modes: ” selection.

4. IF… the computer supports 802.11a/b/g/n Wireless Standards,

 THEN… the computer has the 5 GHz Network Band Capability.


Now in my case my computer supports 802.11a/b/g/n Wireless Standards, but still unable to connect to 5GHz external wi-Fi router. Various resources online point to a ‘Hardware Issue’ and suggest I replace my internal Airport Extreme card on my computer OR buy a latest Wi-Fi router.

Here is what I did, and it immediately resolved my issue


Login in to the Router using IP in my case was . Pls check back of your router

 In control channel option I chose 149 to match my iMac’s Channel configuration. To access press ALT(Option) and click Wi-Fi icon on top bar.

Additional Notes

  • At a minimum, your adapter must support 802.11g/nIdeally, we would like ALL devices to support 802.11a/g/n.

  • If your device only supports 802.11a, it WILL WORK on the LSU wireless network; however, there may be locations on campus where your signal strength might not be ideal.


About the Author

Gurminder is a political scientist and critical thinker based in Australia. He regularly blogs on constructive criticism.