Boot Camp error 0xd000a000-0x40031 during Windows 11 installation on my Mac

You can't install Windows 11 on a MacBook Pro8,1. You can install Windows 10, but you can't upgrade to Windows 11 either. A MacBook Pro8,1 lacks required hardware features related to TPM and Secure Boot; without them, Windows 11 will not install, from upgrade nor scratch.

Boot Camp does not support Windows 11.

Get started with Boot Camp Assistant on Mac - Apple Support

what model-year MacBook Pro 13-in ??

at what stage of that very complicated process are you getting this error?

partitioning the drive to make the Windows partition?

preparing to install?

installing windows?

starting up the installed windows?