KB5029263 caused systems to become unusable due to conflict with 3rd party software

Multiple users reported massive system stability issues to me after installing KB5029263, released yesterday.

It appears that affected users had a utility installed called 'ExplorerPatcher' which was used to revert many Windows UI elements to their Windows 10 appearance and functionality as they found multiple aspects of the UI changes in Windows 11 to severely limit their productivity (users repeatedly complained that things they could previously do in Windows 10 as a single-click, were now only accessible through obscure menus, taking much longer to find and requiring multiple clicks to perform the same action - or in some cases apparently being completely unable to perform the previous action at all).

While Microsoft may disapprove of users trying to escape/avoid changes introduced as part of Windows 11, the issue is that rather than simply blocking ExplorerPatcher from working, KB5029263 makes the machine essentially completely unusable if ExplorerPatcher was installed prior to the update... After installing the update, rebooting and logging into Windows, users found that the while Windows tried to load their start-up apps their Start Menu would disappear every 10-15 seconds and their CPU would be constantly maxed out at 100% - meaning they could not regain control of the system, or stop start-up apps from trying to run and were extremely frustrated as they were stuck in a constant cycle of Windows Explorer trying to load, crashing and trying to load again.

This has caused major disruption to users who were completely unable to work and support staff who ended up having to physically attend affected machines in person because the systems were so severely impacted and were unable to be remotely assisted/controlled.