There are several devices that are incompatible with the 5GHz WiFi frequency. I personally have encountered this issue with my Alcatel 4060A, which runs on Android version 5.1.1. This phone does not support the 5GHz frequency, so I am unable to connect to WiFi networks that operate on this frequency.
Another device that cannot use 5GHz WiFi is the Apple iPhone 4s. This older model of the iPhone does not have the capability to connect to 5GHz networks. I have a friend who still uses this phone, and they have experienced difficulties connecting to certain WiFi networks because of this limitation.
Similarly, the first, second, third, and fourth generation iPod Touch devices from Apple are also unable to use the 5GHz WiFi frequency. These older models do not have the necessary hardware to support the higher frequency, so they can only connect to WiFi networks that operate on the 2.4GHz frequency.
I have also come across the Asus Live and Asus T00I devices, both of which run on Android version 4.4.2. These devices do not support 5GHz WiFi, so users may face limitations when trying to connect to networks that operate on this frequency.
These are just a few examples of devices that cannot use the 5GHz WiFi frequency. It’s important to check the specifications of your device to see if it supports this frequency before attempting to connect to a network that operates on it.