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Call nested .NET dll from C++/CLI Visual Studio project

I'm trying to call a DLL-method from my C++/CLI code in Visual Studio a .NET-DLL (v4.5) called "LicenseCheck.dll". This works fine until this DLL is trying to access another .NET-DLL called "SKCLNET.dll" (.NET v1.0.3705). Meaning the "LicenseCheck.dll" depends on "SKCLNET.dll".
When I try to call the Licensecheck.dll-method "ValidateLicense::GetLicenseStatus()" from a .NET-project it all works fine.
Here is the error I get when running the C++/CLI code:
Unhandled Exception: System.BadImageFormatException: Could not load file or assembly
'SKCLNET.dll' or one of its dependencies. is not a valid Win32 application. (Exception
from HRESULT: 0x800700C1)
at Seat.Core.LicenseProvider..ctor()
at Seat.Core.LicenseProvider.get_Instance()
at LicenseCheck.ValidateLicense.GetLicenseStatus()
at main(String[] args) in C:\Users\deckenf\Desktop\ConsoleApplication1\ConsoleApplication1\ConsoleApplication1.cpp:line 13
at mainCRTStartupStrArray(String[] arguments) in
D:\a_work\1\s\src\vctools\crt\crtw32\msilcrt\mcrtexe.cpp:line 241
C:\Users\deckenf\Desktop\ConsoleApplication1\x64\Release\ConsoleApplication1.exe
(process 33364) exited with code -532462766.
Here the structure of the used dll:
Here the ValidateLicense class in the .NET dll with the function GetLicenseStatus(). This function is being invoked by C++/CLI.
public static class ValidateLicense
{
public static string GetLicenseStatus()
{
return LicenseProvider.Instance.CheckLicense().ToString();
}
}
Here some more details of the SKCLNET assembly:

After two days of investigation, I finally found the problem.
As #Hans Passant worte in the comments, the error in the question is caused because I built the .exe against 64-bit even though SKCLNET.dll requires 32-bit process.
Due to SKCLNET.dll targets .NET v1.0.3705 it was also necessary to add a app.config file to the C++/CLI project and add the useLegacyV2RuntimeActivationPolicy-tag. It is a configuration option in .NET Framework that is used to control the runtime activation policy for applications that use mixed-mode assemblies. In .NET Framework 4 and later versions, the runtime activation policy was changed to a new default behavior. This default behavior can cause some older applications that were designed to work with earlier versions of the .NET Framework to fail.
The last important step was to copy this app.config file after the build in the target path. To do this right click on the C++/CLI project > Properties > Build -Events > Post-Build Event and for the Command Line parameter you paste the following line:
copy app.config "$(TargetPath).config"
This article was helpful to solve my issue.

BadImageFormatException Could not load file or assembly ... An attempt was made to load a program with an incorrect format

I have .NET 5 project which includes C++/CLI DLL, which includes C++ DLL, which includes opencascade DLLs. All these projects are built for the x64 platform. I've published this solution to my local folder and then set up IIS server everything works fine. But when I've tried to upload my project to two different hostings (https://www.smarterasp.net/ and azure) I've got this error. Project crashes when it starts use C++/CLI dll(using namespace C++/CLI). I've also set up x64 platform in azure portal.
I would appreciate any help.

Thank you Joe. Posting your suggestion as an answer to help other community members.
Project crashes because of missing DLL. Run the app and get the error.
Go to the Windows Event Viewer (Start Menu and type "Event"). In the EventViewer, under Windows Logs >> Application, you might see an error message regarding the failure. If the error is a missing DLL, it will typically tell you the name of the DLL as well.
You can refer to Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException), Troubleshooting BadImageFormatException and System.BadImageFormatException An attempt was made to load a program with an incorrect format

VB6 DLL Imported in C# .net project - Class not registered

I need to use a existing old project into new project in .net c#
I've done this:
I compiled the project vb6 in ActiveX DLL, next when I try to add the reference in my project in Visual Studio .net, it don't work (it say that not valid assemble).
I looked for this problem in web and I did found some solution and I tried to import the assembly following directions online and this work fine now
Now the new problem is that when I debug my project I get
Additional information: Retrieving the COM class factory for component with CLSID {0008E6DF-E43B-4DA5-ADFC-2A83E0F04E6C} failed due to the following error: 80040154 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).
Why? How to solve this?

You need to install VB6 dlls. If you don't you need to manually install it. Com Dlls are usually (and VB6 always) self installable.
regsvr32 c:\path\dllname.dll
For some dll files (not VB6)
regsvr32 /i "command line parameters" c:\path\dllname.dll

System.IO.FileNotFoundException error when running Windows Phone 8 application

I have a Windows Runtime Component that uses some native libraries (the PJSIP library). This component is used in a Windows Phone 8 Application and when I try to invoke a function from the native component I get the following error:
An exception of type 'System.IO.FileNotFoundException' occurred in TestingApp.DLL but was not handled in user code
with the Source (at Exception Details) in mscorlib.
Can anyone point out what may be causing this error and how can I find out what is missing actually? When I try to put a breakpoint in my Windows Runtime Component, at runtime, the breakpoint appears as disabled.
Regards,
Tamas

Add the missing dll to the project (like adding a new file) and mark it as content. Then reference the dll from this location. This may resolve your problem.
I guess it is not working as it is not being deployed within your application.

In Visual studio, under the debug menu select 'Exceptions' then in the dialogue that appears enable 'Thrown' for 'Common language runtime exceptions'
Then re-run your application, Visual Studio should break now at the line in the code that is causing the Null Exception.

If you reference a native library, double-check if you also reference C++ Runtime. Under your project in Solution Explorer, right-click References > Add Reference... Go to Extensions and check Visual C++ Runtime Package.

Check the library file you linked, it should be a import library for DLL file.
An import library (.lib) file contains information the linker needs to resolve external references to exported DLL functions, so the system can locate the specified DLL and exported DLL functions at run time.
When app start it find DLL files according to the import library, but there is no such DLL files, so C# throw a FileNotFoundException. Make sure link to a static library

VS2012EXPRESS Ado.Net SQLite missing DLL issue

I'm trying to work out how to use ADO.Net Sqlite in VS2012 Express with no luck.
Things im doing from begining:
Starting new project and installing "System.Data.SQLite (x86/x64)" via NuGet for solution.
Adding using System.Data.SQLite; to directives.
Writing simple code like:
SQLiteConnection sql_sck = new SQLiteConnection("Data Source=test.sqlite;Version=3;New=False;Compress=True;");
Everything seems to look okay, VS recognize class names and changes their colors. However after running the program, in the sql_sck... line, exception is raised - about missing dll ?
An unhandled exception of type 'System.DllNotFoundException' occurred in System.Data.SQLite.dll
Additional information: Could not load DLL 'SQLite.Interop.dll': Could not find specified module. (Exception HRESULT: 0x8007007E)
Any ideas how can I make this work ? Is there anything I've done wrong / any steps missing ?

Somewhere Visual Studio will have created SQLite.Interop.DLL. You need to find that DLL and copy it to the same directory as your application's executable.
I usually add Interop DLLs to my project as a reference and flag them for copying to the output directory in order to ensure that others that use the projects don't forget the manual step.