.NET native images created with NGEN are not loaded

Question

I have used NGEN to create native images of several assemblies used by my application. However, those images are not loaded when running the application and I have no idea why.

This is a typical log from fuslogvw:

*** Assembly Binder Log Entry  (2/05/2012 @ 13:29:04) ***

The operation failed.
Bind result: hr = 0x80070002. The system cannot find the file specified.

Assembly manager loaded from:  C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Running under executable  C:\MyDir\MyApp.exe
--- A detailed error log follows. 

=== Pre-bind state information ===
LOG: User = ***\***
LOG: DisplayName = MyAssembly, Version=1000.0.0.0, Culture=neutral, PublicKeyToken=null (Fully-specified)
LOG: Appbase = file:///C:/MyDir/
LOG: Initial PrivatePath = NULL
LOG: Dynamic Base = NULL
LOG: Cache Base = NULL
LOG: AppName = MyApp.exe
Calling assembly : PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35.
===
LOG: Start binding of native image MyAssembly, Version=1000.0.0.0, Culture=neutral, PublicKeyToken=null.
WRN: No matching native image found.
LOG: IL assembly loaded from C:\MyDir\MyAssembly.dll.

And the information from ngen.exe about that assembly:

C:\MyDir>ngen display MyAssembly.dll
Microsoft (R) CLR Native Image Generator - Version 4.0.30319.1
Copyright (c) Microsoft Corporation.  All rights reserved.

NGEN Roots:

C:\MyDir\MyAssembly.dll

NGEN Roots that depend on "C:\MyDir\MyAssembly.dll":

C:\MyDir\MyAssembly.dll

Native Images:

MyAssembly, Version=1000.0.0.0, Culture=neutral, PublicKeyToken=null

I used the ngen.exe located in C:\Windows\Microsoft.NET\Framework\v4.0.30319\ and my assembly's target framework is .NET Framework 4. I didn't recompile the assembly after having created the native image.

Any help would be appreciated.

Answer 1

Assembly manager loaded from: C:\Windows\Microsoft.NET\ Framework64\v4.0.30319\clr.dll

Your process is running in 64-bit mode, the default with the AnyCPU target on a 64-bit operating system. That requires that you run the 64-bit version of ngen.exe. Be sure to select the proper Visual Studio Command Prompt. There are two, the one that sets up the environment for 64-bit tools is named "Visual Studio x64 Win64 Command Prompt (2010)" in the Start menu.