Win10 cannot run BasicVideoChat sample compiled on Win7.

[fidergo-stephane-gourichon]

List the steps to reproduce the problem.

• Clone from https://github.com/opentok/opentok-windows-sdk-samples
• Compile on Windows 7.
• Run locally. Works.
• Copy to a Windows 10 machine.
• Run.

What is the expected output?

• Program works like in Windows 7.

What do you see instead?

• Program quits without any sort of feedback.
• Using remote debugger shows an exception :

System.Windows.Markup.XamlParseException occurred HResult=0x80131501 Message='L'invocation du constructeur sur le type 'BasicVideoChat.MainWindow' qui correspond aux contraintes de liaison spécifiées a levé une exception.' numéro de ligne '7' et position de ligne '9'. Source=PresentationFramework StackTrace: at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri)

Inner Exception 1: DllNotFoundException: Impossible de charger la DLL 'MFCapturer': Le module spécifié est introuvable. (Exception de HRESULT : 0x8007007E)

What OS and version are you seeing this problem with?

• Compile on Win7 build 7601 SP1 x64.
• Run on Win10 build 1703 x64 (15063.674).

What OpenTok versions were you running (i.e. iOS SDK version, Android SDK version, JS version, etc)

• .NET SDK 2.12.0 from Nuget

What session ID (and archive ID if relevant) did you see this problem on? What token did you use? What date did you encounter this error?

• Happens even before a session ID gets in.

Please attach any relevant logs, screenshots, or any other information that can help solve the problem.

• A WPF hello world works.
• Remote debugging of the WPF hello world works also.

[fidergo-stephane-gourichon]

Compilation output dir shows a x64 subdir with copies of MFCapturer.dll and opentok.dll, suggesting a possible architecture mismatch.

Changed target architecture to see if it changes anything.

Results:

• x86 does not change anything (exact same error message, stack trace etc)
• x64 has a different error.

See upcoming pull request for source code of that attempt.

result_on_project_type_AnyCpu.txt result_on_project_type_x64.txt result_on_project_type_x86.txt

[fidergo-stephane-gourichon]

Attached files 20 minutes ago were using that code: https://github.com/apc-hub/opentok-windows-sdk-samples/tree/github_issue8_attempt_change_target More specifically the 2 latest commits on this tip: https://github.com/apc-hub/opentok-windows-sdk-samples/commit/4d721377e4019340be3fc6cf2f87e50e69c0fa64

[fidergo-stephane-gourichon]

Official documentation OpenTok Windows SDK - for building WebRTC video apps on Windows states:

When creating an installer for your application, add Visual C++ Redistributable for Visual Studio 2015 as an installer package. Use the x86 version, the x64 version, or both, depending on the architecture of your application.

We observed that even with platform-agnostic .NET code, running on a 64-bit OS required installing 32-bit version of the C++ redistributable on the target as for some reason the .NET app is run as 32-bit not 64-bit.