No connection to wifi since updating to Tahoe 26.3.1 on M4 Mini Mac

Give this a try: boot into Safe Mode according to How to use safe mode on your Mac and test to see if the problem persists. Reboot normally and test again.

NOTE 1: Safe Mode boot can take up to 3 - 5 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

NOTE 2: if you have a wireless keyboard with rechargeable batteries connect it with its charging cable before booting into Safe Mode. This makes it act as a wired keyboard as will insure a successful boot into Safe Mode.

ciara_delaney wrote:

Hey folks! I'm still having issues with no/very slow internet connection since installing Tahoe 26.3.1.

I followed the Safe Mode boot and then rebooted my laptop and no luck.

Can I try anything else?

My wifi provider is saying the router is getting like 570Mbps download speed but my laptop only 2Mbps.

Here are some various things that MAY affect WiFi and/or internet performance after an upgrade, when such performance seems to have suddenly degraded:

• VPN - why ... VPNs significantly (factor of 2x or more) slow down connections and the degradation can be a lot worse if the VPN is not fully compatible with the new MacOS (Tahoe). Such incompatibilities are why people report, "I upgraded to Tahoe but then xxx stopped working ..." Plus VPNs are actually not safe because private personal info can be siphoned off the VPN streams and used within the VPN provider or sold by that provider for things that you never agreed to.
• Network security and network "monitoring" apps - why ... incompatibility with Tahoe, or a configuration that worked with older MacOS but does not mesh well with Tahoe due to internal changes in the MacOS.
• Anti-virus - why ... similar to above, incompatibility with newest MacOS, might have worked ok with older MacOS. But antivirus and similar security apps check literally every byte and this slows things down, sometimes they conflict with built in Apple security and this can cause a freeze or dramatic performance degradation.
• "Cleaning apps" - why ... they sometimes delete files that are needed for the MacOS to work properly, in the spirit of "cleaning up" or freeing up space. These "cleaning apps" are notorious for conflicting with new versions of MacOS after innocuous MacOS updates or upgrades.
• Any other third party (non-Apple) security software, especially those that run in the background.

If you are not sure you have these types of things installed, you can download Etrecheck and post its report here following this: https://discussions.apple.com/docs/DOC-250000211

In addition to the above, people who have set up custom DNS addresses or need firmware updates to their router or modem have experienced what you have experienced.

Now that the horse is out of the barn I'll give you this info. It's probably superfluous at this time but here it is: unless you're using a true VPN tunnel, such as between you and your employer's, school's or bank's servers, they provide false security from a privacy standpoint.  Read these articles:  Pubic VPN's are anything but private and Security Risks: The Dangers of Using Free VPNs (eccu.edu).    

Additionally a new study ("Apple Offers Apps With Ties to Chinese Military”) is specifically about VPN apps in Apple’s App Store.

I recommend uninstalling the VPN according to the developer's instructions. Then you can check to see if you've removed all of the supporting files by downloading and running the shareware app Find Any File  to search for any files with the application's or the developer's name in the file name.  For the XXXX files you'd do the following search(es): 

1 - Name contains  xxxx

Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.  

If you get warnings that the file can't be deleted because it is in use or used by another app boot into Safe Mode according to How to use safe mode on your Mac, run Find Any File again and delete from there.

Note:  if you have a wireless keyboard with rechargeable batteries connect it with its charging cable before booting into Safe Mode.  This makes it act as a wired keyboard as will assure a successful boot into Safe Mode.

Glad to hear you got it up and running!

Hey folks! I'm still having issues with no/very slow internet connection since installing Tahoe 26.3.1.

I followed the Safe Mode boot and then rebooted my laptop and no luck.

Can I try anything else?

My wifi provider is saying the router is getting like 570Mbps download speed but my laptop only 2Mbps.