Static analyzer fails on WIX custom install action project: .dll' could not be opened -- 'An attempt was made to load a program with an incorrect format'

Question

On our build system, we use the global setting to code analyze all projects. One of our projects is a C# WIX custom action. This projects causes the build to fail with:
EACustomInstallActions.CA.dll' could not be opened -- 'An attempt was made to load a program with an incorrect format.
The ...CA.Dll target seems to be created by a WIX custom action. Does anybody have already encountered this issue and found a workaround?
Full build output:
<target name="ContractDeclarativeAssemblyCS" success="false">
              <message level="normal"><![CDATA[Build Declarative Contract Assembly for C# D:\EA_MAIN_DB\AMI\bin\Debug\GEHealthcare.Isip.EACustomInstallActions.dll]]></message>
              <message level="high"><![CDATA[C:\Windows\Microsoft.NET\Framework\v3.5\Csc.exe /noconfig /nowarn:1701,1702 /pdb:obj\x86\Debug\Decl\GEHealthcare.Isip.EACustomInstallActions.pdb /errorreport:prompt /warn:0 /define:DEBUG;TRACE;CONTRACTS_FULL;CODE_ANALYSIS /reference:"C:\Program Files\Windows Installer XML v3\SDK\Microsoft.Deployment.WindowsInstaller.dll" /reference:"C:\Program Files\Microsoft SQL Server\100\SDK\Assemblies\Microsoft.SqlServer.ConnectionInfo.dll" /reference:"C:\Program Files\Microsoft SQL Server\100\SDK\Assemblies\Microsoft.SqlServer.Management.Sdk.Sfc.dll" /reference:"C:\Program Files\Microsoft SQL Server\100\SDK\Assemblies\Microsoft.SqlServer.Smo.dll" /reference:"C:\Program Files\Microsoft SQL Server\100\SDK\Assemblies\Microsoft.SqlServer.SqlWmiManagement.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll" /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Data.DataSetExtensions.dll" /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Data.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Drawing.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Windows.Forms.dll /reference:C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Xml.dll /reference:"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Xml.Linq.dll" /addmodule:D:\EA_MAIN_DB\AMI\src\radstore\Installer\EACustomInstallActions\obj\x86\Debug\GEHealthcare.Isip.EACustomInstallActions.CA.dll /debug+ /debug:full /filealign:512 /keyfile:..\..\Common\EAKeyPair.snk /optimize+ /out:obj\x86\Debug\Decl\GEHealthcare.Isip.EACustomInstallActions.dll /target:library /warnaserror- ..\..\Common\GlobalAssemblyInfo.cs CustomAction.cs Properties\AssemblyInfo.cs Resource1.Designer.cs SqlServersSelector.cs SqlServersSelector.designer.cs "C:\Program Files\Microsoft\Contracts\Languages\CSharp\ContractDeclarativeAssemblyAttribute.cs"]]></message>
              <error code="CS0009" file="CSC"><![CDATA[Metadata file 'd:\EA_Main_DB\AMI\src\radstore\Installer\EACustomInstallActions\obj\x86\Debug\GEHealthcare.Isip.EACustomInstallActions.CA.dll' could not be opened -- 'An attempt was made to load a program with an incorrect format. ']]></error>
            </target>

Answer 1

This problem appears to be ongoing 5 years after this thread was started. I have just run into it.
When WiX builds a custom action, the build proceeds as normal and produces a managed code output, say MyCustomActions.dll. Windows Installer doesn't support managed code in custom actions, so the managed code has to be wrapped in an unmanaged native code
wrapper, so in a post-build step, it injects the managed output into the unmanaged wrapper and _that_ then becomes the project's build output and will be named MyCustomActions.CA.dll. I believe that Code Contracts may be trying to open the unmanaged wrapper
file and discovering that it is not managed code ("invalid format").
In order for CCRewrite to work here, it would need to run on the managed code _before_ it gets wrapped in the unmanaged wrapper. I am not sure how we can hook into the build process to get that to happen.
It might be possible to somehow make a WiX Custom Action project by creating a standard C# class library, which would work correctly with CCRewrite, then somehow performing the WiX packaging as a post-build step. I'm not sure what is required though, exactly.
Any ideas?
--Tim Long
Tim Long