Word VSTO 4.0 Addin fails to load: Could not load file or assembly

Question

The issue in short is that I created a Word VSTO addin that works perfectly fine on a number of machines, but fails to load on one machine only. I don't know if the problem is in the assembly name, or there is a missing DLL.

The details of how that is done and the error message are as follows:

1- IDE: Microsoft Visual Studio Community 2013.

2- Office version installed: 2010 for all the machines

3- .NET framework used: 4.0.

4- The target machines have the file vstor_redist.exe installed.

5- The way the VSTO file is installed is through copying the VSTO into program files, then running it. This works for all the machines even the ones that fails to load the add in.

6- The Addin has a ribbon control. Don't know if that has any effect on the matter.

7- Development machine: windows 7 64bit

8- Testing machines: windows 7 64bit. (even the one that fails to load the addin)

9- The error message I am getting when the assembly loads for one machine only is:

Could not load file or assembly 'IDMSWord2010AddinProject, Version=4.3.0.0, Culture=neutral, PublicKeyToken=83105d2b5774c812' or one of its dependencies. The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131047)


************** Exception Text **************
System.IO.FileLoadException: Could not load file or assembly 'IDMSWord2010AddinProject, Version=4.3.0.0, Culture=neutral, PublicKeyToken=83105d2b5774c812' or one of its dependencies. The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131047)
File name: 'IDMSWord2010AddinProject, Version=4.3.0.0, Culture=neutral, PublicKeyToken=83105d2b5774c812'
   at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)
   at System.Reflection.Assembly.Load(String assemblyString)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.ExecuteCustomization.CreateEntryPoint(String entryPointTypeName)
   at Microsoft.VisualStudio.Tools.Office.Runtime.DomainCreator.ExecuteCustomization.Microsoft.VisualStudio.Tools.Office.Runtime.Interop.IExecuteCustomization2.LoadEntryPoints(IntPtr serviceProvider)




************** Loaded Assemblies **************
mscorlib
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1026 (RTMGDR.030319-1000)
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework64/v4.0.30319/mscorlib.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Office.Runtime
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Office.Runtime/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Office.Runtime.dll
----------------------------------------
System.Core
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.233 built by: RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
System
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1026 built by: RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.Hosting
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.Hosting/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.Hosting.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.Runtime
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.Runtime/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.Runtime.dll
----------------------------------------
System.Xml
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1026 built by: RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
System.Configuration
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1015 (RTMGDR.030319-1000)
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Deployment
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1029 (RTMGDR.030319-1000)
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Deployment/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Deployment.dll
----------------------------------------
Microsoft.VisualStudio.Tools.Applications.ServerDocument
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.VisualStudio.Tools.Applications.ServerDocument/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualStudio.Tools.Applications.ServerDocument.dll
----------------------------------------
System.Windows.Forms
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1002 built by: RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System.Drawing
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1001 built by: RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System.Xml.Linq
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.1 built by: RTMRel
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml.Linq/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.Linq.dll
----------------------------------------
Microsoft.Office.Tools
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.Office.Tools/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.Office.Tools.dll
----------------------------------------
Microsoft.Office.Tools.Word.Implementation
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.Office.Tools.Word.Implementation/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.Office.Tools.Word.Implementation.dll
----------------------------------------
Microsoft.Office.Tools.Common.Implementation
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.Office.Tools.Common.Implementation/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.Office.Tools.Common.Implementation.dll
----------------------------------------
Microsoft.Office.Tools.Common
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.Office.Tools.Common/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.Office.Tools.Common.dll
----------------------------------------
Microsoft.Office.Tools.Word
    Assembly Version: 10.0.0.0
    Win32 Version: 10.0.50903.0
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/Microsoft.Office.Tools.Word/v4.0_10.0.0.0__b03f5f7f11d50a3a/Microsoft.Office.Tools.Word.dll
----------------------------------------

Any help or advice is highly appreciated.

Yours sincerely

Answer 1

I found the problem. Office was 64bit, and the addin 32. I totally forgot to check that. Just compiled to 64 bits and all was solved.