So many of you would have upgraded to the latest Mac OS X El Capitan. And while it comes with many advanced features, there are also certain glitches which you might be facing with El Capitan. The most common problem faced by users is Wi-Fi issues on Mac OS X El Capitan. There is poor Wi-Fi connectivity, Wi-Fi does not work in El Capitan or any other such problems which interrupts your work.
In order to fix Wi-Fi issues on El Capitan, there are a few things which you can try out. It is not that hard to fix the problem. Try to ditch old preference files, and then create a new network location with custom DNS settings. An MTU change will solve Wi-Fi problems. But before doing this, you need to backup Mac with Time Machine.
So, first get rid of the current Wi-Fi preferences and make a fresh start
Create a folder on your Mac system to take back up of existing Wi-Fi preferences. Give it a suitable name. Next, switch off Wi-Fi from menu from the top right corner on the Mac screen. From Dock, click on Finder, and hit on Command+ Shift +G keys where you get Go to Folder command.
Select the path – /Library/preferences/SystemConfiguration/ and click on Return. You will be taken back to Folder, where you select these files –
Move these files to the folder which you created initially. You may delete these files. Next, restart Mac. If you turn on the Wi-Fi and there are problems still, then you have to create a new custom network.
Create new Wi-Fi network with custom DNS
For this, first shut down all apps that are running on Wi-Fi. Click on Apple menu followed by System Preferences. From system preferences, click on Network. Next, click on Wi-Fi from the list, followed by Location menu and choose Edit Locations. Click on “+” sign in order to create a new location, give a suitable name for network and hit on Done button.
Beside the Network Name, join the Wi-Fi network. Type the router password, and click on Advanced button on the Network screen. Click on TCP/IP tab, followed by Renew DHCP Lease button. When a warning message pops up, hit on Apply and continue.
Now, click on DNS button from Network screen and “+” from left lower corner under DNS Servers. Type 220.127.116.11 and 18.104.22.168 in the black space under DNS Servers. Next, hit on Hardware button, and under Mac Address, choose Manually. In the MTU tab, select Custom from the drop down menu and type the MTU number – 1453, and click on OK. Finally, click on Apply button to create a new Wi-Fi network.
Your Wi-Fi should work fine after this. You can also check the speed to verify if internet is working or not.