Linux dual-boot killed, Explorer crashes, UAC broken

September’s Patch Tuesday for Windows 11 22H2/23H2 was a greatest hits compilation of breakage. Linux dual-boot systems stopped booting entirely, greeted with “Verifying shim SBAT data failed: Security Policy Violation” — Microsoft’s Secure Boot update decided that Linux wasn’t secure enough to exist. File Explorer crashed when opened from the taskbar. Run as Administrator (UAC) broke due to DLL issues, meaning you couldn’t elevate privileges to fix the other problems. Enterprise systems hit Unified Write Filter deadlocks with SCCM. SAP EasyDocuments stopped working. The workaround for the Linux issue involved disabling Secure Boot entirely, which rather defeats the purpose of a Secure Boot update.