XnViewMP does not start

[dr.mike]

Windows 11-25h2 (updates complete) yesterday for the first time refused to start xnviewmp (x64) claiming mdk.dll contains an error.
Tried uninstall (incl. deleting remaining files)/fresh install with no change.
Tried to run the portable version, same problem.

[xnview]

are you able to start XnConvert?

[dr.mike]

Yes, starts and converts. (portable)

[xnview]

Yes, starts and converts. (portable)

Strange, i've tried on a clean Windows 11-25h2 with all updates, and no problem to start it.

[dr.mike]

I deactivate smart appcontrol before I start xnviewmp, it works, and a activate sac again ... until the next start of xnviewmp.
I do not trust ms too much, will need to find out if I need smart app control

[dr.mike]

Finished updating my PCs, same rufus-stick for fresh 25h2 installs. SAC seem to be like Artificial Madness - only 1 out of 3 PCs reports mdk.dll as faulty.