After upgrading to the new macOS Mojave, Wifi functions may not work correctly. Whatever the problems are, the following solution would help you to get rid of troubles.
Firstly, if it’s possible, try to connect to another WiFi network (Personal Hotspot is an easy example) to find out the cause is your MacOS Mojave or the Router.
Secondly, it’s very important that if you have installed any network manager applications such as Little Snitch, you should remove all, then reboot your Mac to see positive results.
How to fix Wifi not working correctly under MacOS Mojave?
I would recommend to Turn Off then Turn the WiFi back On. If the problem remain the same, hopefully the following solutions would helps.
Solution 1: Reboot your Mac.
You may have done this natural solution already. If the problem remains the same, take the solution 2.
Solution 2: Remove the Mac’s Bluetooth potentially corrupted files
This will actually make a new Wi-Fi Configuration in macOS High Mojave. How to locate then remove the corrupted files?
Library/Preferences/ or Library/Prefernces/SystemConfiguration/ Locate and remove the following files if existing (you may need to make a backup of them before deleting):
com.apple.airport.preferences.plist com.apple.network.eapolclient.configuration.plist com.apple.wifi.message-tracer.plist NetworkInterfaces.plist preferences.plist
Reboot the Mac at normal then see if the problems are going to be gone!
Solution 3: Use Apple’s Wireless Diagnostics
How to call Apple’s Wireless Diagnostics under MacOS Mojave? From the screen, hold the Option key while point the mouse to drop down the WiFi icon at the Top-right corner.
Solution 4: Customize your New Custom Network Location
- Click on Apple menu to select “System Preferences”
- Select the “Network” panel then choose “Wi-Fi” from the list
- Next, just pull down the “Location” menu and select “Edit Locations”.
- You now can make a new network location: Click the [+] plus button, make name like “AppleHintNetwork” then click on “Done”.
- Alongside Network Name, pull down the dropdown menu and select the wi-fi network to join, enter the password if applicable
- Next, click on the “Advanced” button (look at the above image for the button).
- Next, Choose the “TCP/ IP” tab then click on “Renew DHCP Lease”
- Next, from “DNS” tab, you will see the “DNS Servers” section. To add a new the DNS, click on the [+] plus button then add the following IP addresses (i am using Google DNS servers, you can use the same or use another one):
- Now from the “Hardware” tab and set the ‘Configure’ option to “Manually”, modify the “MTU” option to “Custom” and set the number to “1453”
Finally click on OK then Apply button.
The above steps would fix almost all common issues with Bluetooth you may face with the new macOS Mojave.