Windows 11 24H2 ran into difficulties with some Ubisoft games, and therefore the upgrade was blocked for users with those titles installed - but the good news is that a fix is now in place for two of said games.
The affected Ubisoft games were three Assassin's Creed outings (Valhalla, Origins, Odyssey) along with Star Wars Outlaws, and Avatar: Frontiers of Pandora. Those games would freeze up (with a black screen crash in some cases), and this could happen when loading, or during gameplay.
A hotfix was pretty swiftly released for Star Wars Outlaws, and now Avatar has one, as well, so owners of those titles are free to upgrade to Windows 11 24H2 (as long as their PC doesn't have any other compatibility issues that could lead to a block being put in place by Microsoft).
If you've got either Star Wars Outlaws or Avatar installed, make sure they are patched to version 1.4.0 and version 1.2 respectively to get the fixes.
Unfortunately, those who have one of the mentioned Assassin's Creed games are out of luck, but we'd expect a cure will be in the pipeline before long.
It's worth noting that while the fixes for Outlaws and Avatar mean the nasty crashes have been banished, those running Windows 11 24H2 may still encounter performance hiccups in these games.
Microsoft cautions that whatever you do, if you've got one of the affected Assassin's Creed games installed, don't try to fudge a 24H2 installation and sidestep Windows Update by using the media creation tool, for example. Just wait for these games to get their patches.
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