SMB sharing can no longer be used by Windows 11 24H2

Hello dear Nix community,

until today my nixos server was running fine. All devices could access the SMB shares, MacOS, Android, Windows. But since today it no longer works with Windows. Problem could have been the update last week since apparently the signing of SMB connections seems to be mandatory (Even though the comments say that this has been the case for 5 years).

The error message that Windows immediately brings when clicking on the server in the network environment is #80070035 “Network path not found”

Other connections from the Windows 11 computer to the server such as ssh and http work without any problems and the Samba server also works without any problems, MacOS and Android can still access the share.

I have tried to activate the signing with the following configuration:
server signing = mandatory
client signing = mandatory

Here is my complete smb config:

{ config, ... }:

{
  services.samba-wsdd = {
    enable = true;
    openFirewall = true;
  };

  # Curiously, `services.samba` does not automatically open
  # the needed ports in the firewall.
  networking.firewall.allowedTCPPorts = [ 445 139 ];
  networking.firewall.allowedUDPPorts = [ 137 138 ];

  services.samba = {
    enable = true;
    enableNmbd = true;
    securityType = "user";

    extraConfig = ''
      # Server-seitige SMB-Signatur erzwingen
      server signing = mandatory
      client signing = mandatory
      # Aktiviert die Unterstützung für SMB2 und SMB3
      server min protocol = SMB2
      server max protocol = SMB3
      # Erlaubt sichere Negotation von Verbindungen
      client min protocol = SMB2
      client max protocol = SMB3

      workgroup = WORKGROUP
      server string = BFDS
      netbios name = BFDS
      server role = standalone server
      map to guest = bad user

      log file = /var/log/samba/smbd.%m
      max log size = 50
    '';

    shares = {
      Rob = {
        path = "/bfds-nix/rob";
        browseable = "yes";
        "writable" = "yes";
        "guest ok" = "yes";
        "create mask" = "0644";
        "directory mask" = "0755";
        "force user" = "smbuser";
        "force group" = "smbuser";
      };
    };
  };
}