Ventura 13.3.1 Update causes WiFi fail

I'm not sure if this has actually fixed it. However so far I'm seeing better results, including routable IPv4 on my Mac. I ran though these instructions about dropping the networking plist files which results in the OS having to rebuild them from scratch. I didn't both to compare before and after, I just dumped the old ones and let it do something new. So far no flickering and full networking has been function:

1. Quit out of all active apps on the Mac, including System Settings
2. Turn Wi-Fi OFF by going to the wi-fi menu bar (or Control Center) and toggling the wi-fi switch to the off position
3. Open Finder in macOS, then go to “Go” menu and choose “Go To Folder”
4. Enter the following file system path:
5. /Library/Preferences/SystemConfiguration/
6. Hit return to jump to that location, now locate and select the following files in that SystemConfiguration folder
7. com.apple.wifi.message-tracer.plist
8. NetworkInterfaces.plist
9. com.apple.airport.preferences.plist
10. com.apple.network.eapolclient.configuration.plist
11. preferences.plist
12. Backup the files and then delete them.
13. Reboot your mac
14. For me, wifi turned on and it remembered my SSID + Password, reconnected, all seems good so far.

It's been a few hours but so far so good.

My WiFi (and everything else) worked just perfectly after the 13.3.1 update, and I don't see a great mass of problem reports here which I would expect if there was a buggy release. That makes me think the few victims in this thread got hit with either a corrupted download (unlikely because it would not verify correctly), or something specific to their individual settings and/or WiFi router. Note that although the problem described may sound like the same issuer, it could be 2 different problems causing the same outcome for the 2 different users.

My first thoughts are to simplify things as much as possible in an attempt to locate the cause of failure;

> Try to determine the cause of failure - at least to which stage is falling over. For example, is the WPA password getting accepted or rejected?

> Reboot (power cycle) the router and everything connected to it. Including any remote WiFi extenders. If possible during testing, shut down any possible conflicting devices like printers

> Try renaming the WiFi (SSID) just in case they did something unexpected like creating a new Reserved Word within MacOS.

> Check WiFi settings for anything which might have got mangled in the update, including the TCP/IP v4 network addressing (Auto, manual, correct subnet mask etc).

> Check the WiFi security scheme in use, looking for a mismatch between the router and client devices. Something like defaulting the newly upgraded client device to WPA3 when the router is on WPA2 is not unheard-of.

> For the purpose of testing only, try resetting the WiFi to be an Open system (Not WPA, etc) just to see if you can connect.

> Check for firmware updates available on the router.

It might be worth comparing notes about the make and model of WiFi router or other access points being used, just in case there is something unexpected there.

If the router and MacBook both have a regular (wired) Ethernet ports it might be worth testing a wired connection.

Users in our environment were experiencing this problem as well. It seems to stem from the computer trying to utilize a wired and wireless connection at the same time. Disabling WiFi, while leaving a wired connection connected, or disconnecting a wired connection while leaving WiFi enabled, has fully resolved the issue from our environment until Apple can release an update with a permanent solution.

I have been experiencing this issue on a MacBook Pro (16-inch, 2019) (2.6 GHz 6-Core Intel Core i7). WiFi connects briefly and sometimes even passes traffic, but disconnects very quickly. Have tried the suggestions in this thread (manually connecting, disabling other network adapters, turning off Bluetooth, trying to renew DHCP lease, etc.) to no avail. And like other reports, there have been no changes to my WiFi setup (eero mesh), and dozens of other devices on my network are able to connect, including other iOS and macOS devices.

On the weekend, I dug out an Ethernet-to-USB-A adapter, plugged it into a USB-A-to-USB-C dongle, then used it to connect to my wireless router directly. I upgraded to Ventura 13.4. Things seem to be much better now, although it still takes a few tries to establish a stable WiFi connection. But there is no more endless loop of disconnecting and brief reconnecting. In fact, I'm typing up this post from the laptop and the WiFi has been stable for the past half hour.

So, if you have the ability to connect to a network via a wired connection, try upgrading to Ventura 13.4?

A fix to try (worked for me, at least)

• System and Settings
• Privacy and Security
• Full Disk access
• select VPN and Security filters (Norton etc)

if that doesn't work

• Systems and Settings
• Network
• VPN and Filters
• Remove filters (such as Norton)

This worked for me.. hope it does for you too

You have done a lot to diagnose the problem, there are a couple areas that have not been mentioned:

• Reboot computer in Safe Mode?
• Restart router?
• Any VPN installed?
• Did you have the "Wifi Recommendations" in the Wifi menu or did you "Open Internet Diagnostics" by holding the Option key and clicking the Wifi icon? Normally if a problem is detected you will see "Wifi Recommendations" in the Wifi menu with suggestions.

so mine worked after I switched the LAN connection to inactive - seems to interfere, when I use Wifi, but have LAN enabled. It's not something I turned on, so either it wasn't an issue before the update or the update "changed" the setting.

Thanks, I removed the network and rebooted. Reconnected and now seems to be stable again.

UPDATE: I posted last night about having this exact same issue with my new mini after doing the update. Today, I called apple support and they were able to fix it remotely. They will guide you through the process. It won't take more than a 1 minute to fix the issue. Hope this helps!

open system preferences, go to Wifi, then click on details. Then TCP/IP, then Renew DHCP. That is all I did on my end, however keep in mind that apple support helped remotely, which means they were connected to my Mini... I can not tell you if they did something on their end as well to fix the issue. Best is to call apple support.

Forget the network and connect again

Ventura 13.3.1 Update causes WiFi fail - Apple Community

I tried this fix, it worked for me.

Hello,

I just wanted to add to this with a bit more info. I work in IT, I've been scratching my head on this one tonight too. My Mac has been fine up to this update for 13.3.1. My Mac is exhibiting similar issues, but only when using IPv4. All other devices on my network operate properly. I've checked / rebooted my hardware firewall etc...

Locally, IPv4 on the main subnet works. IPv6 works locally and globally from my machine. It's only IPv4 traffic that seems to fail to route despite having a proper ipv4 gateway. Hotspot with my iPhone will work for IPv4. It would seem that this update may have a potential for a bug in it with IPv4 traffic routing. I've tried turning off the firewall (confirmed with getsocketfilterfw -getglobalstatus - it's off). DNS resolution works only because I have an IPv6 DNS server that is responding and routable. Any other tips that might lead me somewhere?

I've rebooted the Mac. In recovery mode, IPv4 works perfectly fine over wifi. Wired in over thunderbolt dock in a normal boot, same result, IPv6 routes properly but IPv4 doesn't. I'm running a Google Mesh wifi point in AP mode with a pfSense hardware backend. I'm also experiencing random flickering black screens. To me, this is a broken update. For lack of free time required to reinstall Ventura from scratch, I can't prove it's a broken application of the update. At some point when I have the free time I'll either reinstall or take my chances with a zero day exploit and rollback to 13.2 I've seen other posts related to flicking black screen and lack of connectivity after this update.

Similar issue after upgrading my M1 Macbook Air to Ventura 13.3.1 today. Internet works ok, then after a while no connection to internet. I only use IPv4. The WiFi is still connected but no internet connection. It looks like DNS resolution is not working. If I put 1.1.1.1 in the browser it shows me the CloudFlare page but it wont resolve any DNS name. I can also ping IPs from a command prompt.

I've disconnected and reconnected WiFi but it doesn't fix the issue. Only a reboot will give me back internet access but then after a while it will stop again. I believe it may be after my laptop gets woken from sleep mode (after I leave it for a while), but I'll have to test it out further. I only updated it today and its happened twice so far.