System.Data processor architecture set to AMD64

Question

TFS have issued the following warning:

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Microsoft.Common.targets (1605): There was a mismatch between the processor architecture of the project being built "MSIL" and the processor architecture of the reference "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\System.Data.dll", "AMD64". This mismatch may cause runtime failures. Please consider changing the targeted processor architecture of your project through the Configuration Manager so as to align the processor architectures between your project and references, or take a dependency on references with a processor architecture that matches the targeted processor architecture of your project.

Both "Release" and "Debug" configurations are set to use "Any CPU" as an active solution platform.

I took a copy of System.Data.dll into the TEMP folder and extracted information about this assembly through PowerShell:

function ScanAssembly($assemblyPath) {
    [reflection.assemblyname]::GetAssemblyName($assemblyPath) 
}

$assemblyPath = "C:\TEMP\System.Data.dll"

$assemblyInfo = ScanAssembly($assemblyPath);
$assemblyInfo | fl;

I got the following output:

Name                  : System.Data
Version               : 4.0.0.0
CultureInfo           : 
CultureName           : 
CodeBase              : file:///C:/TEMP/System.Data.dll
EscapedCodeBase       : file:///C:/TEMP/System.Data.dll
ProcessorArchitecture : Amd64
ContentType           : Default
Flags                 : PublicKey
HashAlgorithm         : SHA1
VersionCompatibility  : SameMachine
KeyPair               : 
FullName              : System.Data, Version=4.0.0.0, Culture=neutral, 
                        PublicKeyToken=...

For some reason, the ProcessorArchitecture for this assembly is set to Amd64. I'm confused as to why it's set to Amd64, because I'm running a 64-bit operating system on an Intel processor.

These warnings are not show stoppers, but I'm struggling to understand as to why we are seeing them. If I understand this correctly, the configuration is set to any CPU, when one of the assemblies is compiled for Amd64, which implies that it will no longer work on any CPU - it'll work only on 64 bit CPU. Why the System.Data.dll is built for Amd64 is beyond me.

Thank you.

Just in case someone gets confused, AMD64 has little to do with Intel vs AMD. It just means "64-bit". It's the same thing with "x86" being able to run on modern CPUs. — Mike Caron

Rebecca Campbell Rebecca Campbell · Accepted Answer · 2013-10-30T20:39:09

You're correct about why these errors are occurring. If a referenced assembly targets a specific framework, the compiler warns that your application can't run on "Any CPU" because the referenced assembly has limitations.

We had this issue on our test and production servers with System.Data and other DLLs. We resolved it by installing the .Net Framework SDK. To do that:

Find the correct SDK. Our environments are set up with Windows Server 2008 and .Net Framework 4.5, so we used the Windows 8 SDK.
Install only the .Net Framework 4.5 SDK (after you accept the license, there's a screen with several checkboxes; I only left the last one checked).

The SDK adds a new version of System.Data.dll in C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5. Examining that assembly, you can see that the ProcessorArchitecture is set to None.

Name                  : System.Data
Version               : 4.0.0.0
CultureInfo           :
CultureName           :
CodeBase              : file:///C:/Program Files (x86)/Reference\Assemblies/Microsoft/Framework/.NETFramework/v4.5/System.Data.dll
EscapedCodeBase       : file:///C:/Program%20Files%20(x86)/Reference%20Assemblies/Microsoft/Framework/.NETFramework/v4.5/System.Data.dll
ProcessorArchitecture : None
ContentType           : Default
Flags                 : PublicKey
HashAlgorithm         : SHA1
VersionCompatibility  : SameMachine
KeyPair               :
FullName              : System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089

The other option is to configure your project to target 64-bit processors if that's an option, but our team chose to go the SDK route.

System.Data processor architecture set to AMD64

1 Answers