Ventura DNS problem turns macbook pro into expensive paperweight

Ollie2710 wrote:

Other odd thing I noticed is that for home sharing, it appears my macbook fancied renaming itself macboopro2 or something equivalent in home sharing (possibly to not confuse with wife's identical?)

macOS will rename the Mac if it detects another one with the same exact name. Depending on the router's configuration it may retain an old connection for this laptop under that name and the router does not see this laptop as the same. May actually be clue.

Just saw something that says apple may be squashing external security software? I use Sophos, and two different VPNs, one for work, th eother mine, neither are turned on.

Just because they are not actively running does not mean they have not modified system settings which are stilll active. Uninstall Sophos by following the developer's instructions since anti-virus apps, cleaning/optimizer apps, and third party security software are not needed on a Mac.

I know that Ventura seems to have removed Network Locations, so you may want to try creating another macOS user account, logging out of your current user, and logging into the new user account to see if it makes any difference.

I can't "reinstall" Ventura, because these macbook pros don't have RJ45 jacks, just thunderbolts? Without wifi, I can't download anything?

At the risk of sounding like a n00b, I now wonder if plugging a thunderbolt tu USB into my router might connect me to the interwebs again?

You can try using a USB-C to Gigabit Ethernet Adapter both to access the network while booted into macOS and also for trying to access recovery mode. Unfortunately I have seen some accounts where third party USB-C to Gigabit Ethernet Adapters may not always work at least for Internet Recovery Mode (all seem to use the Realtech chipset), but I haven't tried in a while since I had to resort to using an unwieldy setup utilizing the official Apple USB-C to Thunderbolt 2 Adapter combined with an Apple Thunderbolt 2 to Gigabit Ethernet Adapter since some things I need to do won't work with the third party adapter.

If you have access to another Qualifying Mac, then you can use the other Mac to create a bootable macOS USB installer using the instructions in this Apple article:

Create a bootable installer for macOS - Apple Support

A strange something writes an alternative DNS address into your WIFi setting.

(I haven't figured out which process yet.)

Go to System Preferences/Network/WiFi/"Details" of the active WiFI network/ there on "DNS".

Delete all weird DNS addresses and add your own trusted one (from your provider or an open one).

That solved the problem at least for now.

You don’t need any of these “security” programs.

Effective defenses against malware and other threats: https://discussions.apple.com/docs/DOC-8841

Please post screenshots of the DNS and Proxies sections in System Settings->Network: select Wifi, then click on Details...