Chosen Solution
I bought this asus vivobook 15 model X512FJ-EJ228T. When starting to use it I connected with my 5.0ghz wifi network without problems. I used it for a few days until I decided to check if everything was up to date on it. I downloaded drivers directly from the asus website at this link: ++https://www.asus.com/us/Laptops/ … /HelpDesk_Download/++ I installed the network driver and continued using the computer normally, during the working day he simply disconnected from wifi and did not accept but connect to wifi 5.0ghz, giving the message in the attached image. (unable to connect to this network) Now it only accepts to connect on 2.4ghz network. Already tested my wifi network with 2 smartphones, another notebook and with a dongle, but without the dongle the notebook will not connect to wifi 5.0ghz. I want to solve this problem for him to reconnect to 5.0ghz network naturally.
Update (01/08/2020)
Hi @kelvinslc , Did you try rolling back the drivers to the previously installed drivers to see if the 5GHZ WiFi now worked? Did you end up here to get your drivers? (choose model and OS and then scroll down to Wireless to find the drivers) Did you check whether you downloaded the drivers for an ASUS VivoBook 15 X512FJ or an ASUS VivoBook 15 X512FJG as they have different Wireless adapters installed? The ASUS VivoBook 15 X512FJ has an Intel adapter and the ASUS VivoBook 15 X512FJG has a Qualcomm Atheros adapter Have you checked in Device Manager which WLAN adapter is installed? Here’s a link to the very latest Asus WLAN drivers for all adapter types used by Asus, which may help.
downgrade the driver or wait for the next update
