Why is my network messed up after update to windows 11 24H2

See

Win11 24H2 Installed, now no network sharing https://www.elevenforum.com/t/win11-24h2-installed-now-no-network-sharing.29035/

especially this -

Computer Configuration, Windows Settings, Local Policies, Security Options
Double click on Microsoft Network Client: Digitally sign communications (always)
Double click on Microsoft Network Client: Digitally sign communications (if server agrees)
Set both of these to "Disabled"
Click on OK.

Please let us know if this helps.

Samba drives are gone, no longer able to connect back. Forget enabling insecure sign-in, or changes of protocol (1, 2, 3), or whatever been suggested in this or parallel threads. It's just broke.

The whole network connection is unstable, snapping at random times for a minute or so - mildly noticeable when browsing, but enough to terminate SSH link with a server. Remote work has never been so enjoyable.

It's been long months since first reports about connectivity issues in 24H2 appeared on this forum. Microsoft not only did little to fix the issues, it does not even trouble itself to mention them [https://learn.microsoft.com/en-us/windows/release-health/status-windows-11-24h2]. Wow! Congratulations for complacency. Head in the sand. Instead it lets its users wander through endless fora where one encounters multiple hacks that supposedly work, but in fact more than often just make the OS more vulnerable, or break something else entirely. Experimenting like that before figuring out what is the actual cure, if any, one can easily cripple the entire system. But maybe that's intentional, huh?

It takes a bit of digging to get to the technical page [https://learn.microsoft.com/en-us/windows/whats-new/whats-new-windows-11-version-24h2] where changes in the SMB support are mentioned. But the issue is probably elsewhere, as the error suggest the requested site could not be found, not that there's protocol problem.

I did a simple change. Instead of wasting time on all these permutations and combinations, I just clicked on 'Go back to previous build' in Restore and went back to Windows 23 H2. Anyways Windows 11 is a useless OS. Fedup of using this OS. If it gives more issues I prefer going back to Windows 10.

I dont have Norton, but apart from that everything your write is familiar!

They also totally messed up my email (Outlook on Thunderbird). Recent "improvements" mean that this no longer works without me getting down and dirty with various help sites...

Horrible! Why cant this biggest software company it the world sort this!

Ive reverted to 23H2 which at least resolve this issue.. And wont make a move until 25H2 arrives. If that doesnt work then perhaps the time has come to say farewell to Micro$oft!

I had the same problem when 24H2 was installed on one of my computers. I installed it on two computers. Computer number 1 shares the files. Computer number 1 can access computer number 2 shared files (although that isn't the directly we are trying to share). Computer number 2 cannot access shared files. Norton also decided that computer 2 was a malicious attack and blocked it. Computer number 2 went back to the prior version and can see shared files and is no longer considered to be a malicious attack by Norton. Both computers only have 2 logins. My windows login and my husband's windows login. I have logged into both computers with my password to link up the computers (this used to work). Neither files have a guest login enabled. I tried all of the listed steps on this thread but nothing worked except for removing the updated version of windows.

On another note computer number 3 on the network which is still using Windows 10 could always see the shared files and was not interrupted with the update on computer 1.

The change in how Norton viewed the connection isn't something that was mentioned and seems odd it went away removing the update. What in the update would tell another windows computer that it is malicious.

Also, even after I temporarily disabled the block on computer 1 in Norton, Norton still blocked the access (listed on the block list and gave me an alert). I added computer 2 to the exclusion list and it still blocked it as well.

Just saying... I miss the days of the Home Group.