Wi-Fi is unstable after macOS Tahoe update on MacBook Air

You could also try these

Forget your Network and delete the Wi-Fi configuration files

Go to System Settings > Network > Wi-Fi, click the three-dots button next to your network, and select Forget This Network.

From the previous tip in the thread

To reset network preferences on a Mac by deleting .plist files, disable Wi-Fi, open Finder, press Command+Shift+G, enter /Library/Preferences/SystemConfiguration/, and delete files like com.apple.airport.preferences.plist, NetworkInterfaces.plist, and preferences.plist to the Trash. After restarting the Mac, your system will regenerate these files with default settings. 

Steps to Reset Network Preferences

1. Turn off Wi-Fi: Click the Wi-Fi icon in the menu bar and select Turn Wi-Fi Off. 
2. Open Finder: Click the Finder icon in your Dock. 
3. Use "Go to Folder": Press Command+Shift+G to open the "Go to Folder" dialog box. 
4. Enter the Path: Type or paste /Library/Preferences/SystemConfiguration/ into the box and press Go. 
5. Delete .plist Files: Locate the following files in the SystemConfiguration folder and drag them to the Trash: 

• • com.apple.airport.preferences.plist
  • com.apple.network.identification.plist (if present)
  • com.apple.wifi.message-tracer.plist (if present)
  • NetworkInterfaces.plist
  • preferences.plist

1. Empty the Trash: Right-click on the Trash icon in the Dock and select Empty Trash. 
2. Restart Your Mac: Go to the Apple menu and select Restart. 
3. Re-enable Wi-Fi: After your Mac restarts, turn your Wi-Fi back on from the menu bar. Your Mac will automatically create new default .plist files, and you'll be able to reconnect to your network. 

Reset your Location Services 

1. Go to System Settings > Privacy & Security > Location Services.
2. Turn off Location Services.
3. Next, restart your device from the main Apple menu.
4. When your Mac relaunches, turn your Location Services back on.

Use Terminal to reset your DNS and network stack

1. Open Terminal from Finder > Applications > Utilities.
2. Run this command: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
3. Enter your admin password and press Return.

You can try this. No guarantees it will work.

To reset network preferences on a Mac by deleting .plist files, disable Wi-Fi, open Finder, press Command+Shift+G, enter /Library/Preferences/SystemConfiguration/, and delete files like com.apple.airport.preferences.plist, NetworkInterfaces.plist, and preferences.plist to the Trash. After restarting the Mac, your system will regenerate these files with default settings. 

Steps to Reset Network Preferences

1. Turn off Wi-Fi: Click the Wi-Fi icon in the menu bar and select Turn Wi-Fi Off. 
2. Open Finder: Click the Finder icon in your Dock. 
3. Use "Go to Folder": Press Command+Shift+G to open the "Go to Folder" dialog box. 
4. Enter the Path: Type or paste /Library/Preferences/SystemConfiguration/ into the box and press Go. 
5. Delete .plist Files: Locate the following files in the SystemConfiguration folder and drag them to the Trash: 

• • com.apple.airport.preferences.plist
  • com.apple.network.identification.plist (if present)
  • com.apple.wifi.message-tracer.plist (if present)
  • NetworkInterfaces.plist
  • preferences.plist

1. Empty the Trash: Right-click on the Trash icon in the Dock and select Empty Trash. 
2. Restart Your Mac: Go to the Apple menu and select Restart. 
3. Re-enable Wi-Fi: After your Mac restarts, turn your Wi-Fi back on from the menu bar. Your Mac will automatically create new default .plist files, and you'll be able to reconnect to your network. 

This is really nuts that the manual IP seems to be the fix. After replacing routers, modems, trying every Wifi frequency, channel, clearing out all wifi preferences, moving my router around the house, this SEEMS to be the only thing that's fixed it, that is, assuming it holds. For it to work I had to use "DHCP with manual address" and also assign the IP from my TPLink router DHCP Reservation settings. Only doing it on the Mac side had no effect, while using the full "Manually" setting resulted in no internet access.

After following a strange recommendation in this thread, I created a new test Mac user account, and after a few hours of testing, performance seems to be...perfect??

Can some others test this so we can see if it's a viable solution?

If so.....

1. what the he¬¬
2. maybe something in the user account gets screwed up in the update? maybe it can be found/fixed/cleared?
3. can a user account be duplicated? or is there some other easy way to completely migrate everything from one account to another on the same computer? i doubt it...probably would need to be backed up, wiped, brought back w/ Migration Assistant, but would that bring the corruption with it?

I also actually tried testing using fast user switching, leaving my original/real account still logged in and "switching" to the test account, and it did NOT work, I had the problem on the test account as well. So apparently still having the original account open in the background was causing a problem.

Have you updated to Tahoe 26.2 today. Not that I think it will help the problems you are having since it is beginning to sound more like a faulty hardware problem. Hardware does fail on Mac's like on anything that man builds. On a old Mac I had some years ago the Bluetooth module went south on me.

I would suggest that you first download EtreCheck and run it to see if it can find anything wrong with the Mac

. It's free to use. https://etrecheck.com/en/index.html. Here is a link written by some with a lot knowledge about using it. Once you have run it you can post the results (In Etrecheck, click Share Report > Copy Report,) to a comment

2019 Intel mac here, running Tahoe.

Wi-fi to home router is broken after update but works on many other wireless networks. At home, I have resorted to manually assigning my IP address which solves the issue but indicates there's something wrong with the DHCP process. We have about 12 other devices running just fine on this 5Ghz Wifi network. This is the first time owning a Mac that I've had such an awful experience with a new update. Restarting router, deleting .plist files, removing networks, did not solve the issue—just a straight up manual setting of my IP. Wild.

This is intriguing, and baffling, at the same time. I'm going to give this a try as soon as I post this, but my assumption is the same as yours--"something" on our current user account is cause this. So, what happens if you take your new test user account and simply sign into your Apple Account (via System Settings)? Does the old behavior return in that case?

You probably see where I'm headed with this. If a vanilla/virgin user account does not exhibit the problem, but the same account immediately has the problem after nothing more than signing back into your Apple Account, then the problem is going to follow us even if we migrated to a new Mac user.

This is starting to remind me of an issue I chased years ago on my Mac where wireless would go wonky on a predictable cadence. Actually, this happened in two different cases for me. One case was ultimately due to awdl0 (ugggghhhh.... don't get me started on this one.) and the second was due to a Location Service running a background wifi scan. The channel scans hurt--anything causing our wireless radios to "pause" and switch channels is going to be noticeable at some point.

Anyway, talk is cheap. I'm going to try some things on this path you paved and see where it goes... thanks!

@alirezazgr and @ffjxc -- Maybe try the macOS 26.2 public RC? I upgraded to it last evening because of hoping it would help with some of the same wireless woes you've described here. I figured it couldn't make anything worse (although I know that is often not true).

I seem to be having a better wireless experience at this point on it. Maybe you'll have the same luck?

Ok, little bit more data:

• updated to 26.2
• repeated the whole network files/settings reset process such as this (and left Location Services disabled for testing)
• ran Disk Utility First Aid from recovery partition
• logged in w/ my Apple Account on my new test user

Behavior is exactly the same: bad on my current user, perfect on my test user.

I hear where you're coming from on the hardware problem angle. Hardware can, and does, fail at times.

But, I have been running the 26.2 betas for a bit and now the RC/GA. It didn't fix the wireless issues for me, though others' experiences could be different I suppose. I can tell you with confidence this issue presents itself across multiple Apple devices in my home, all of which are running version 26 of their respective OS flavor (iPads, iPhones, MacBooks). It would be a pretty wild assumption that half-dozen+ Apple devices in my house all developed a hardware issue at the same time.

I'm going to try @Shade of Blue's suggestion of trying a new user account. May not be part of any solution in the end, but it feels like something worth trying.

Having the same issues. Out of the blue the wifi just stops working get the spinning colorful ball. I can't force quit apps, & have to do a force restart by holding my finger on the power button. Happens either at initial startup or a few hours into using my macbook air M2 but every single day. Just performed a force restart after using my mac for over an hour.

Think Apple must have brought over Microsoft Techs bc this never happened in the past. Roll out of new os' were seamless. Now they are always buggy. Apple needs to do better.

Spent 1.5 hrs w apple support & got nowhere. They couldn't even tell if it is a known issue to be addressed in the next update.

For anyone keeping track, the manual IP only worked for a little while, now it's back to the same old (running a 2020 M1 MBP on 26.1. Wifi performs well enough for most purposes but trying to use my Shadow remote gaming PC, the latency and packet loss is all over the place. Guess I'm stuck on ethernet for now, or using my old 2013 MBP that has no problem at all.

I tried everything said here even set static IP for my devices but both my iPhone SE 2020 and my. Mackbook Air 2020 M1 are having problems with my home wifi...

Is there any other fix I can try?

I'm still keeping a close eye on this thread. It is unbelievable to me that this type of regression exists, but it's very present for me and very painful to work with at times. I SSH into a number of devices in my home for various reasons and the latency and packet loss makes that experience maddening.

Not sure what more to try at this point. I'm presently testing with 5Ghz disabled across the four APs I have in my home. Wondering if the same behavior still occurs on 2.4Ghz. Shows how desperate I am for a fix, I suppose.

FWIW, this is my machine:

- **Model Name**: MacBook Pro

- **Model Identifier**: Mac15,9

- **Chip**: Apple M3 Max

- **Memory**: 48 GB

- **macOS Version**: macOS 26.2 (25C56)