1. The issue is that I run Windows server 2022 as a host of a virtual machine (on windows 11 or MacOS), and this image is used for docker: mcr.microsoft.com/dotnet/sdk:5.0-windowsservercore-ltsc2022 And when I run regsvr32.exe s for a certain dll file, it fails with exit code 3 inside containers, which means “LoadLibrary failed” according to https://devblogs.microsoft.com/oldnewthing/20180920-00/?p=99785.

2. When I run regsver32.exe OUTSIDE container, it fails, too. But if I remove the s option, then it shows this dialog https://i.sstatic.net/HlVX9FbO.png, and after selecting ‘ok’, it doesn’t fail. After this, regardless of s option, it doesn’t fail.

3. There is a similar, but different, question: “/questions/77885374/regsvr32-fails-in-windows-docker-container”. --user "NT AuthoritySystem didn’t work. Also Removing the UAC didn’t work. And when I tried the RegsvrCli tool from https://github.com/smourier/RegsvrCli, it is interesting:

Using regsvrcli.x64.exe, on both machines (vm & container), it returned Calling LoadLibrary("C:UsersAdministratorFluencyDirectdownloadAMEAnyModalEditCtrl2.dll") returned error 0x800700C1 (-2147024703): %1 is not a valid Win32 application.

Using regsvrcli.x86.exe, vm says Registering c:UsersAdministratorFluencyDirectdownloadAMEAnyModalEditCtrl2.dll' returned: 0x00000000 (0) while container says Calling LoadLibrary("C:UsersContainerAdministratorFluencyDirectdownloadAMEAnyModalEditCtrl2.dll") returned error 0x8007007E (-2147024770): The specified module could not be found. even though the dll file is there and has the same size.

Could anyone answer how this is so and/or how to fix this issue?