Windows 11 expands memory integrity. Games and drivers may run into problems

Microsoft is widening the reach of memory integrity in Windows 11, also known as HVCI or "core isolation". The change reaches users through update KB5132061 from 10 November 2026.

How memory integrity works

The feature checks which code is allowed to run in the system kernel. It uses virtualisation (VBS and a hypervisor), so that the check is moved into an isolated environment. Gaining access to the kernel therefore does not automatically allow arbitrary code to run. The protection makes many attack methods harder, but it does not stop every one of them.

What is changing

According to Spider's Web (a report from 3 September 2026), the feature was due to switch on automatically from October on most computers. Antyweb reports that an optional update from 28 October enabled this protection only on eligible devices, and that it is now reaching people who skipped it earlier. It will not necessarily switch on for everyone.

Windows checks first whether the configuration is ready. If a user had previously turned memory integrity off, the update is not meant to override that choice. The same applies in businesses: if an administrator disabled the feature across a group of devices, the update will not force it back on.

Performance and compatibility

Microsoft says the feature runs more efficiently on Intel processors from Kaby Lake onwards and on AMD processors from Zen 2 onwards. Older chips can only emulate it, and according to Antyweb this carries a performance cost.

HVCI can also cause problems with drivers and software, particularly those working close to the kernel. Anti-cheat tools in games have sometimes been affected. Many of these issues can be fixed by updating programmes, games and drivers. Windows also has a mechanism that reverses the automatic switch-on when a problem arises with a driver needed for startup.

What this means for you

The change applies to Windows 11 computers wherever they are, so people living in the UK and in Poland may notice it after updating. Gamers on older hardware are probably the most likely to feel the effect. If a game runs worse or a driver stops working with the system, users can check the core isolation setting and decide whether to keep it on. Antyweb notes there is no single answer for everyone, as it depends on the configuration and on the individual user's experience.