I'm in exactly the same position after fighting with trying to install 24H2 for over a week with about 10 attempts under my belt.
Secure boot is enabled by default in BIOS.
Used Revo Uninstaller to uninstall any unnecessary software including third party security software.
Used CC Cleaner to ensure that all drivers and software are completely up to date.
Insured that all my temporary and page file are located on Drive C and that it was not encrypted.
Ensure that the Alienware R13 had the latest firmware, 1.20.0.
System upgraded flawlessly from Windows 10 20H2 to 22H2, then Windows 11 22H2 and 23H2. No issues, kept all files and software intact.
Used the Windows 11 image from MSDN downloaded early December 2024. Then switched to using the Microsoft Media Creation site to download the latest Windows 11 ISO. Same results.
Used Rufus, and my tried-and-true Powershell methods to prepare USB used for all media upgrades including splitting the wim file for a GPT FAT32 USB.
In every test case, the machine will run through its installation it will sit for a couple hours at 75% and then proceed to complete and reboot. Upon reboot the machine will appear to initialize some files then reboot a few times within 10-30 seconds pulses and then the machine will claim that one of the fans is failing to spin up and the system diagnostics will prevent the machine from booting further unless I select CONTINUE. This is the first telltale sign that this update has failed. Telling the machine to CONTINUE will push the machine into a rollback and the 23H2 will be restored.
In every case the final diagnostics after the rollback is the same...
We couldn't install Windows 11
We've set your PC back to the way it was right before you started installing Windows 11.
0xC1900101 - 0x40017
The installation failed in the SECOND_BOOT phase with an error during BOOT operation.
Searching these error codes comes across some people having success by disabling secure boot and it leads me to believe that Microsoft is playing with TPM and Secure Boot requirements and the Alienware firmware does not know how to accommodate the changes.
https://forum.level1techs.com/t/bitlocker-win11-pro-24h2-edition-secure-boot-is-mandatory/220427
https://learn.microsoft.com/en-us/windows/security/hardware-security/tpm/switch-pcr-banks-on-tpm-2-0-devices
https://support.microsoft.com/en-us/topic/kb5025885-how-to-manage-the-windows-boot-manager-revocations-for-secure-boot-changes-associated-with-cve-2023-24932-41a975df-beb2-40c1-99a3-b3ff139f832d#bkmk\_install
I give up.
P.S. Also tested the MSDN version Windows 11 24H2 on a couple other Dell workstations and the machines upgraded perfectly fine. Rufus was used to disable some of the initial pre-checks. Additionally, installing a different SSD into Alienware R13 and installing Windows 11 fresh from this USB worked fine.
I would also vote, similar to above, that installing fresh and reinstalling all applications and configurations on a system that has seamlessly upgraded through other feature updates is unacceptable.