The module was expected to contain an assembly manifest

Question

I have a project in c# that uses c++ library and some dlls. When I run it it works great.

The library is Awesomium, contains both c++ library and c# wrappers

When I create reference to this project from my ASP.NET MVC 4 project I get the following error:

Exception Details: System.BadImageFormatException: Could not load file or assembly 'file:///D:\Projects\Development\ProGamers\GamingSite\bin\avcodec-52.dll' or one of its dependencies. The module was expected to contain an assembly manifest.

Things I've tried:

1. Coping the dlls, but it still doesn't work (The file exists).

2. Registering it in the GAC but I've got the same error there.

3. Make sure using .NET Framework 4.0 (and not client profile)

4. 2 files with the same dll/exe name causing conflict - I dont have it.

5. Change the platform of the solution to AnyCPU/Mixed Platforms.

Stack Trace:

[BadImageFormatException: Could not load file or assembly 'file:///D:\Projects\Development\ProGamers\GamingSite\bin\avcodec-52.dll' or one of its dependencies. The module was expected to contain an assembly manifest.]    System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +0    System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +34    System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +152    System.Reflection.RuntimeAssembly.InternalLoadFrom(String assemblyFile, Evidence securityEvidence, Byte[] hashValue, AssemblyHashAlgorithm hashAlgorithm, Boolean forIntrospection, Boolean suppressSecurityChecks, StackCrawlMark& stackMark) +102    System.Reflection.Assembly.LoadFrom(String assemblyFile) +34    WebActivator.ActivationManager.Run() +190  [InvalidOperationException: The pre-application start initialization method Run on type WebActivator.ActivationManager threw an exception with the following error message: Could not load file or assembly 'file:///D:\Projects\Development\ProGamers\GamingSite\bin\avcodec-52.dll' or one of its dependencies. The module was expected to contain an assembly manifest..]    System.Web.Compilation.BuildManager.InvokePreStartInitMethodsCore(ICollection`1 methods, Func`1 setHostingEnvironmentCultures) +550    System.Web.Compilation.BuildManager.InvokePreStartInitMethods(ICollection`1 methods) +132    System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath) +90    System.Web.Compilation.BuildManager.ExecutePreAppStart() +135    System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException) +516  [HttpException (0x80004005): The pre-application start initialization method Run on type WebActivator.ActivationManager threw an exception with the following error message: Could not load file or assembly 'file:///D:\Projects\Development\ProGamers\GamingSite\bin\avcodec-52.dll' or one of its dependencies. The module was expected to contain an assembly manifest..]    System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9850940    System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +101    System.Web.HttpRuntime.ProcessRequestInternal(HttpWorkerRequest wr) +456 

Answer 1

I found that, I am using a different InstallUtil from my target .NET Framework. I am building a .NET Framework 4.5, meanwhile the error occured if I am using the .NET Framework 2.0 release. Having use the right InstallUtil for my target .NET Framework, solved this problem!

Answer 2

BadImageFormatException, in my experience, is almost always to do with x86 versus x64 compiled assemblies. It sounds like your C++ assembly is compiled for x86 and you are running on an x64 process. Is that correct?

Instead of using AnyCPU/Mixed as the platform. Try to manually set it to x86 and see if it will run after that.