In order to install Windows update/upgrade successfully, you will need at least 20GB of free space on your hard disk. Failed in Second Boot phase with a mistake during Boot operation. Certain security settings can also interfere and lead to repeated errors or The procedure should be straightforward, and all that you need is Windows 11 installation media and a PC that meets the hardware requirements. Knowing that a rollback has occurred is not a big deal since I know that already. The firewall can potentially stop the upgrade.