Only specific OS freezes on certain internet connections

I solved this issue the following way: (On Sierra 10.12.6 Macbook Air mid 2013)

0. As soon as your computer restarts from one of the freezes, disable the Wifi so it doesn't freeze while you do the following steps.

1. Disable the Wi-Fi ipv6 -> This seemed to work, but as soon as I enabled my VPN connection it was back to freezing.

networksetup -setv6off Wi-Fi

(See this for details: http://osxdaily.com/2014/04/18/disable-ipv6-mac-os-x/)

2. I realized I also needed to disable ipv6 from the VPN. For this, I looked up the name of my VPN in System Preferences > Network

In my case:

networksetup -setv6off ExpressVPN

During the whole process I was able to use the internet via Ethernet and iphone tethering. I didn't need to disable ipv6 from those options, only the connections going via Wifi needed ipv6 disabling.

After this, Wifi was back to work and I got no more freezes.

Note (Don't do this!): I tried the approach of deleting /Library/Preferences/SystemConfiguration folder I found in some other places, but this didn't work for me. Instead, it made Finder crash continuously and I had to restore from Time Machine.

References: wifi - Macbook freezes when connected (connecting) to new wireless router - Ask Different

Rasstarr, I can't tell you how pleased we were to find this answer. I'm embarrassed to tell you I've been to the MAC repair store 7 times in the last month, trying to remedy this problem; only to end up doing my work while connected to their problem-fee network. I was about to buy another computer after paying AT&T $45 for a diagnostic fee (of course they didn't solve it). THANK YOU ! ! !THANK YOU ! ! !THANK YOU ! ! !THANK YOU ! ! !THANK YOU ! ! !

Thanks very much for this. I have been suffering with my old (2008) MacBook Pro freezing on both wifi and ethernet at various locations for several months, also turning wifi on or off made it freeze. Usually necessitated an SMC reset each time.

I even went to the trouble of replacing the RAM. But having switched both Ethernet and Wifi IPv6 to link-local, all the problems have gone away. At least I now have some spare RAM and a Mac that works!

Well, I have also to thank you, as I was going to get crazy!

I wanted though to ask you why that happens and how is possible that internet blocks and freezes an entire computer? Also, if that happens with specific ISPs , maybe a good idea would be to list them all here. My provider is Plusnet (Uk).

I'd like to thank you for this (disabling ipv6) - worked perfectly (Macbook 3,1, OSX 10.5). Was seriously confused as to what it could be.

Conflict is with a DLink router, and freezing occurred on both Airport and ethernet.

Thanks for confirming this issue. I recently was learning IPv6 and practicing to setup IPv6 over IPv4 tunneling. I happen to find my mac freeze sometime when I plugged in the cable. Finally I narrowed it down to my new setup of IPv6. I got IPv6 working but still it is annoying it might locks up my mac. I am running 10.6.

Thank you from Russia! You saved plenty of my time. I changed my wireless modem to a new model and experienced this problem. Rebooted my iMac dozens of times. Thanks for posting the fix!!!

Brilliant! I spent the last week going crazy trying to fix the spinning beach ball but couldn't understand why it only happened when I was at home. I was drinking too much coffee in Starbucks just so I could get online without my computer freezing and the Local Apple shop must have thought I was stupid to keep taking my 'frozen' computer to them only to have it restart in the shop with no problem. Thank goodness I don't need to buy a new computer ...... yet!

Thank you! You saved the day! We had a project that needed to be uploaded before a deadline. We had this exact problem and couldn't find the answer. Good on ya mate!

THANK YOU! This worked like a charm. I was so exacerbated that the freezing only happened when I was at home that I thought the new place I moved into was some kind of bermuda triangle for macs (roommate's PC worked fine). So glad to find your posting!!!

I am so thankful for this. I almost had my ISP deliver another modem which would have given me the same problem and cost hundreds of dollars for nothing

Ok, question. Setting the ipv6 to off & turning airport off worked; however, when I turned airport back on it did the freezing thing again. I had to power down my Mac & turn airport off again to get it to work right again. Is there a way to stop the freezing with airport on?

I would like to give a big thank you as we were driving ourselves crazy over here for 3 weeks trying to figure out what was wrong. i had to carry my iMac through the mall to the Apple store, which got heavy I must say, just for them to then hook it up & whammo, it works with no problems. I was all happy thinking I had my Mac back, get home, plug it in, & nada. I could have screamed. Hubby is a windows kinda guy & Macs are foreign to him, but he still drove himself crazy trying to figure this out. Phone/internet company had no clue. The computer repair guy around the corner wanted over $100 just to come out. In the end it was two simple steps. Are you freakin kidding me? Hubby is going to flip. Very happy I have it back though, at least partially.

I want to thank you so much for this! You have saved me much frustration! I came back from the US a couple of weeks ago, turned on my computer when I arrived back at my apartment and my computer started to freeze continually every time I opened the internet. For a few weeks I thought my computer had gotten damaged on the flight. I continued to test out my computer with other internet connections and every time it worked perfectly, thus leading me to this thread. The problem is now fully resolved! Many thanks! 🙂

Thank you, Thank you, Thank you! I have been so perplexed with this for weeks. I even hauled it in to the Apple Store - where it worked fine of course. This WORKED - thanks!