Hi.
It just happened to me on a freshly installed and subsequently patched W11 Machine which is set to boot PXE primarily, that after the Patch, it wouldn't even start PXE any longer. I have a (very blurry) image of the error. Essentially, it doesn't like the NBP file (ZCM 24.02).
"NBP file downloaded succesfully.
Verifying shim SBAT data failed: Security Policy Violation
Somethung has gone seriously wrong: SBAT self-check failed: Security Policy Violation"
Like I said, the only change between succesful PXE imaging via Winpe , and this message on booting, was Windows Updates for the fresh W11.
Disabling Secure Boot helps. Just notifying.