How do I resolve 'LoadLibrary failed with error 193: %1 is not a valid Win32' error message in Simulink 8.1 (R2013a)?

I have an S Function block in which I am trying to load a DLL generated using Microsoft Visual Studio. I am using 64 bit MATLAB. I am able to generate the .mexw64 file. However, when I try to simulate the Simulink model that contains the S Function block, I got the following error in a popup window:

'LoadLibrary failed with error 193: %1 is not a valid Win32'

Answer 1

[MathWorks Support Team]

The "LoadLibrary failed with error 193: %1 is not a valid Win32" means that a 64 bit operating system is trying to load a 32 bit Win32 file.

You can check the bitness of the DLL file using dumpbin. You can do so at the Windows Command Prompt:

C:\> call "C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\vcvarsall.bat"

C:\> dumpbin \headers DLL_filename

Fixing the error involves one of the two following options:

1. Run the application under 32 bit MATLAB.

2. Compile the .dll as a 64 bit application.

a. In Visual C project properties, change the Platform to x64.

b. In Visual C project linker library path properties, add "C:\Program Files\Microsoft SDKs\Window\V7.1\Lib\x64 so kernel32.lib is found."