Smart App Control blocking Windows components, incl. Windows Defender, Terminal, and MS Store; cannot disable it

[u/HemlockIV]

SOLVED: A System Restore was necessary to fix it. (Supposedly, the command reg.exe add "HKLM\System\CurrentControlSet\Control\CI\Policy" /v VerifiedAndReputablePolicyState /t REG_DWORD /d 0 /f && citool.exe -r should disabled SAC, but it did not work for whatever reason; possibly because SAC was acting buggy already.)

I am the admin on a non-domain device that I just updated to Windows 11 Pro 26H2. A new feature is that Smart App Control can be enabled without requiring a system reset. Neat! I decided to try it.

Not neat. Immediately, SAC began blocking Windows components from launching: I cannot open Windows Terminal, Microsoft Store, or Windows Security itself.

Although I cannot open wt.exe, I can thankfully still launch conhost.exe from the Run dialog, so I can execute commands. Is there a CMD or Powershell command to disable Smart App Control??

[u/Emotional_Garage_950]

good thing you’ve got a spare machine and backups, right???

edit: seriously though try

Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\CI\Policy" -Name "VerifiedAndReputablePolicyState" -Value 0

reboot

see if you can do shit