Here's the explanation since update KB5083769

[lavande]

read to the end:
Microsoft: Windows 11 KB5083769, KB5083631 block backup apps like Macrium, here's why.
https://www.neowin.net/news/microsoft-wi...e_vignette

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This should interest the Hasleo team.

[garioch7]

@lavande,

Thank you for sharing that information.  I am very certain that it will be of interest to the Hasleo Team, and to the HBS user community.

Have a great day.

Regards,
Phil

[admin]

@lavande,

Thank you for sharing. Here is Microsoft's original article:
https://support.microsoft.com/en-us/topi...3c1b1aa9d0

April 2026 Windows security updates introduce protections to known vulnerable ke…
Skip to main content Microsoft Support Support Support Home Microsoft 365 Office Pr…

psmounterex.sys is a driver provided by Macrium Reflect. Hasleo does not use it, and neither do any other backup software. psmounterex.sys is just a driver for mounting disk images, it shouldn't cause backup failures (especially VSS failures). Microsoft's approach is truly puzzling. Are their developers out of their minds?

Best regards,

[lavande]

Things should generally improve for Windows 11.

"Microsoft is reportedly working to fix Windows 11's most annoying flaws — wants to restore the operating system's reputation"
https://www.tomshardware.com/software/wi...-in-the-os

Microsoft is reportedly working to fix Windows 11's most annoying flaws — …
Apparently, complaints from the Windows Insider community have reached a tipping po…

[admin]

Things should generally improve for Windows 11.

"Microsoft is reportedly working to fix Windows 11's most annoying flaws — wants to restore the operating system's reputation"
https://www.tomshardware.com/software/wi...-in-the-os

It feels worse and worse, the actual experience is more like "reverse optimization".