How to Fix Slow Internet Problems After macOS Sierra‎ Update

It’s hard to stay away from upgrading your Mac computer to the latest version of macOS Sierra. There are so many cool features and a redesigned interface that every Mac users should experience.

Just like most people, I decided to give it a try and my Macbook Air upgraded to the new version without any problem.

While other blogs have reported a handful of challenges with macOS Sierra, I only saw one, and it has to do with the internet speed on my Mac. After getting the upgrade, I tried to browse the web using Google Chrome, but the internet speed was very slow. General fixes like rebooting the modem didn’t do the trick.

It was evident that my Wi-Fi was slower than usual and updating to macOS Sierra definitely caused this problem. Even some static pages take forever to load.


How to Fix Slow Wi-Fi after macOS Sierra upgrade

After doing some research, I found a solution to the slowness of my Wi-Fi. If this happens to you in macOS Sierra, try the following.

  1. Turn off your Wi-Fi completely
  2. Create a new folder on your desktop and name it
  3. Open your Finder (the smiley face icon on the dock) and press Command + Shift + G. All three keys at the same time
  4. This will pull up Go To Folder. From there type in: /Library/Preferences/SystemConfiguration/
  5. Look for the following files:,,, NetworkInterfaces.plist, preferences.plist
  6. Copy and paste them to the folder you created in Step 2
  7. Then delete those .plist from the SystemConfiguration


One more step before you’re done. Restart your Mac computer. Once it’s rebooted, connect to your Wi-Fi again. My internet connection went back smoothly. I can feel it’s much faster than before. If you continue to encounter slow Wi-Fi connection, visit a nearby Apple Store for further assistant.

Disable Automatic Download in macOS Sierra

Did you know that Apple will automatically download and install macOS Sierra on your Mac computer? Well, now you know, and it will be executed starting today (Oct. 3). Luckily, users are allowed to turn this feature off.


Here are a few reasons why:

  • Background downloading can effect overall internet speed
  • It’s at least a few GBs in storage space

To disable macOS Sierra automatic download, go to System Preferences > App Store. Uncheck the option for “Download newly available updates in the background.”

From now on, if you want to check for new updates or get the update just go to the App Store and perform it manually.

HSTS/SSL Certificate Error

So here’s what happened earlier.

I opened up my MacBook Air and tried to take advantage of the free Wi-Fi at one of my local Starbucks. After that, I launched Google Chrome and boom, an error message popup.

Your connection is not private or secure…This site uses HTTP Strict Transport Security (HSTS)…normally uses encryption (SSL) to protect your information.

Although this particular problem do not deal with your Wi-Fi being slow it’s possible for some users to get the same issue after upgrading to macOS Sierra.

How to Fix SSL certificate problem

  1. Click on the Wi-Fi icon on your Mac’s menu bar
  2. Select Open Network Preferences..
  3. Click Advanced and then choose the current network that you’re connecting to
  4. Select the Subtract sign next to the addition sign and click Ok
  5. Stay on the same Network Preferences… page and click on Wi-Fi on the left side
  6. And click the subtract sign at the bottom > Apply
  7. Now, click the addition sign and choose Wi-Fi under Interface and Service name
  8. Click Apply to save all your changes

Re-connect to the Wi-Fi network that you were having trouble with earlier. This will help you fix the SSL error in Google Chrome.


I don’t know if there is any better solution than the method I instructed above. If you found any, please let us know using the comment section below.

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  1. Good luck with that! I had this problem with El Capitain and three successive Mac Book pro mid 2015 models. I had to get a refund in the end. Apple can’t fix the problem and if it isn’t sorted for Sierra then they can’t fix it. It has been an open ticket with their engineers for months on El Capitain.

  2. I was having odd problems for a while with WiFi speeds — typically at 80 Mbps but was topping out at 4 or 5.

    For me the fix was changing the channel on my Apple Airport Extreme via this article @ Macworld:

    I did this and next speed check I was up to 90 Mbps.

  3. The file com. apple. plist network. identification. is not in the folder. I see a file with the name: com. apple. network. eapolclient. configuration.

    This replaced the “… network. identification. plist”?
    Can I remove it?

  4. The file is not in the folder of macOS Sierra.

    I see a file named:

    Is this file a replacement for the file and can I also remove this file?

  5. My WiFi stopped working entirely once I upgraded to Sierra. I think my MacBook was timing-out during the DHCP requests? Deleting these files and rebooting fixed the problem. Thank you!

  6. I had issues with Sierra refusing to recognise some of Wifi access points, but not all. I could not work out why, and tried all the above fixes. Finally cracked it when I found that Sierra had turned IPv6 to AUTOMATIC. As soon as I set it to LOCAL LINK ONLY, all my troubles went away on wifi. Sierra now running like a train on my MacBook Air 2012.

  7. can’t find neither “” nor “”, do i just ignore this?

  8. I followed these instructions — moved and then deleted the files, but I couldn’t find the file so I restarted. Then I saw that I should have removed the file, so in a second attempt, I moved and deleted that single file, and restarted again.

    Wifi is still bad, when I go to random sites like, I’m getting the bare bones HTML, but Gmail etc works. What should I do?

  9. Quick update. Some servers seem slow, but others are working fine. Ran a speed test via Google and my times are excellent, but I don’t know what I can’t hit other servers. Odd.

  10. I also am missing the file but I don’t have the one that other people are mentioning ( file).

  11. Hi Rasel. There are some good fixes here. But, if they haven’t fixed your Mac OS Sierra problems, you can try some additional fixes discussed here

  12. I don’t know you guys but I’ve been having this issue since I upgrade to Sierra. Now I’ve seen this thread a looooot over the internet. Same instructions same files to remove. In the first thread I saw there was a file that I had to remove and that file was nowhere on my Mac mini. ( I even used the spotlight nowhere to be found. So I delete all files in the folder. Mac came back on everything new files but same issue. Then I see this thread without that file that I never found before . I did the same thing by this instructions and same issue still there. Seems like theres no fix to it. Btw internet is high speed and router is not that far away. So I guess im going to ethernet the heck out of my Mac. Unfortunately . Bad apple, bad apple!

  13. And yes …I did tried everything I can. Memory, close to router , router configuration, Mac performance, my question is why would I need to mess with my Mac if wasn’t like that before Sierra?. Btw Mac mini (Late 2012) 2.3 GHz Intel Core i7 8 GB 1333 MHz DDR3
    intel HD Graphics 4000 1536 MB Sierra ver. 10.12.1

  14. Thanks for this. My wifi and internet speed is much, much better now. I think it is not the best speed possible so I will look further for more improvements.

  15. Thank you for this great idea! Before this I had (when it was better) 13 ms ping and download around 50 Mbit. Now I have 8 ms with 87 Mbit and way more stable.

  16. I have tried this method on my husband’s macbook air several months ago. Then about a month ago, my macbook pro 2013 had the same issue and I used this same method to resolve it. But it’s come back again, now both our macbooks aren’t connecting to the internet, despite full bars on the wifi signal yet our devices (ipad and iphones) connect to the internet fine. This method doesn’t work anymore, I’ve tried it over and over again, at least 10 different times in the past 48 hours. Is it really an unsolvable Sierra OS problem?

    • I hear ya! I thought of two suggestions. 1. Reset your macOS or downgrade it back to older OS. Give either a try and let me know.

      • After 2 hours on the phone with an apple support rep and exhausted all options… She had the brilliant idea to use my time machine hard drive. I went into the Library folder from a week ago, copied those plist files and pasted them into my current Library folder. Restarted the computer and ta da! It was a miracle…

        This method is not working on my husband’s Macbook Air though… still trying to figure that one out.

  17. Didn’t work for me. Instead it messed up something else and every time I go to a new website, my browser opens a second tab full of commercials.

  18. hoping someone can troubleshoot for 4th gen ipad will connect to free/unsecured wifi, but will not connect to password protected wifi.. either at home or elsewhere. i type the correct password in and it says it is wrong. Went to apple store yesterday, they did a reset, but still it doesn’t work. since they have unprotected wifi in the store, it worked and they couldn’t see what it’s doing for me at home.

    any ideas???!

  19. hey bro, i did the first method, and yes the conection is smooth, better than before. But i have another problem, i have random ping spikes that goes even to 2000, like when sierra was realesed, any thoughts?

  20. On my 27-inch iMac Retina 5K, The “assist me” button in Preferences>Network is missing and the “Revert” and “Apply” buttons are greyed out. Need help.

  21. Worked like charm in macbook air 2017 model high sierra,
    ping tim was like 300 ms before now its 20 ms and also download upload speed it showing correctly. what a relief

  22. The fix for the slow internet after the macOS update SO worked! I too was ready to reinstall. Thanks for the information! This is gold!

  23. Hello It is super helpful, deleting the files. however, my problem is that the files keep coming back and it seems that I have to keep doing that! Any solution that is once and for all? Thanks !

  24. I may have followed instructions wrong and deleted “ because all the others came back but it…

  25. I don’t have any of those files there. But have something like …could’ that be new names with latest update?

    Mackbook Air 2012 or something like that

  26. It did work for me for a while, but now the files keep on coming back, how is this possible. All auto downloads are shut off and these files keep on coming back. I have deleted them at least 10 time and they come back on restart of the Mac.

  27. THANKS SO MUCH for this fix! I thought it was an ATT issue! But in searching for fix for the Spotlight issue with Sierra realized that the internet issue was also with Sierra! Your fix worked perfectly!!


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