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Windows 10 try to load non-existing mun files

I have a problem with time-consuming network Windows operations. When I load my .dll resorces, Windows 10 is trying to load matching .dll.mun files (it's not from my software, it's system specific) for all the dll's loaded in my program, from non existing folder SystemResources. Windows expects SystemResources folder to be located next to folder which contains my software. When dll's are on network share this causes access to IPC$ share, on some systems it's very time-consuming, which is very problematic.
Problem is visible in simple, clean mfc application. Below is trase from procmon, where it's visible that system is trying to access IPC$ share multiple times, where searching for mun files in SystemResources folder, which does not exist.


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In earlier Windows builds, icon resource files were embedded in some DLL in the directory


Since Windows 10 version 1903, they have been relocated to:


There is now a new extension for these files .mun instead of .mui

Could you please tell us, which version of win10 are you using ? If you are using an earlier version of Windows, I suggest you try to update the system.

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I do understand that new Windows 10 is loading mun files for system dll's from C:\Windows\SystemResources, this is fine. But why system is trying to load those files for my dll's files? Why it's looking for SystemResources folder next to folder with executable?, it this case \\localhost\SystemResources.
My version of Windows 10: 20H2

Is there any way to block this behavior?

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Could you please provide some steps and a code sample that help us reproduce the issue? I try to run an MFC application, couldn't reproduce the issue.

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