“An attempt was made to load a program with an inc

Question

I'm calling functions from a 32-bit unmanaged DLL on a 64-bit system. What I get is:

BadImageFormatException: An attempt was made to load a program with an incorrect format. (Exception from HRESULT: 0x8007000B)

At first, I had my projects set to the Any CPU platform, so I changed them both to x86, but this error is still occurring. That's really the only fix I know for this.

The DLLs aren't corrupt or anything, because I can use them with other programs (that I don't have the source to). I thought that perhaps it wasn't finding a dependency, but I checked and they're all there. Plus, wouldn't it throw a DllNotFoundException in that case?

What else can I do? And before you say "Use a 64-bit unmanaged DLL instead," let me point out that there isn't one. ;)

Answer 1

Somehow, the Build checkbox in the Configuration Manager had been unchecked for my executable, so it was still running with the old Any CPU build. After I fixed that, Visual Studio complained that it couldn't debug the assembly, but that was fixed with a restart.

Answer 2

I got this issue solved in the 'Windows' way. After checking all my settings, cleaning the solution and rebuilding it, I simply close the solution and reopened it. Then it worked, so VS probably didn't get rid of some stuff during cleaning. When logical solutions don't work, I usually turn to illogical (or seemingly illogical) ones. Windows doesn't let me down. :)

Answer 3

I just had this problem also. Tried all the suggestions here, but they didn't help.

I found another thing to check that fixed it for me. In Visual Studio, right-click on the project and open "Properties". Click on the "Compile" (or "Build") tab and then click on "Advanced Compile Options" at the bottom.

Check the dropdown "Target CPU". It should match the "Platform" you are building. That is, if you are building "Any CPU" then "Target CPU" should say "Any CPU". Go through all of your Platforms by making them active and check this setting.

Answer 4

Also see this answer, which solved the same problem for me.

Posted by Luis Mack on 5/12/2010 at 8:50 AM I've found the same problem, only for a specific project when compiling on a 64-bit machine. A fix that SEEMS to work is to manually alter one character in the image stream EVERY TIME the usercontrol or form is edited in the designer

 AAEAAAD/////AQAAAAAAAAAMAgAAAFdTeXN0ZW0uV2luZG93cy5Gb3JtcywgVmVyc2lvbj00LjAuMC4w

Change to

 AAEAAAD/////AQAAAAAAAAAMAgAAAFdTeXN0ZW0uV2luZG93cy5Gb3JtcywgVmVyc2lvbj0yLjAuMC4w

That is 00LjAuMC4w back to 0yLjAuMC4w at the end of the line (00 back to 0y)

Answer 5

I was able to fix this issue by matching my build version to the .NET version on the server.

I double clicked the .exe just to see what would happen and it told me to install 4.5....

So I downgraded to 4.0 and it worked!

So make sure your versions match. It ran on my dev box fine, but server had older .NET version.

Answer 6

In my case, I am using a tiny .exe that reloads the referenced DLLs via Reflection. So I just do these steps which saves my day:

From project properties on solution explorer, at build tab, I choose target platfrom x86