wpf throwing an difference parsing xaml includes winforms user control

i have wpf app creates winforms user control i have combined controlling c++/cli. app goes parse xaml sure window, throws an exception. information appears rather abbreviated, nonetheless says:

a initial luck difference form 'system.windows.markup.xamlparseexception' occurred presentationframework.dll

additional information:   current win32 application. (exception hresult: 0x800700c1)  blunder markup record 'osgviewer;component/osgviewerwin.xaml' line 1 position 9.

i commented out winforms control xaml all loads fine. i figured maybe constructor control doing something bad, i put breakpoint it, nonetheless breakpoint does seem enabled i start run app, never hit, i know meant dll containing line loaded. many approaching means an difference thrown an vigilant form dll instantiated - physique object's constructor couldn't found.

i have finished successfully opposite digest past, i pulled opposite winforms user control app, instantiated xaml, works fine.

so it's something dll. i have anxiety dll wpf c# app, i bucket dll vigilant browser mandatory classes namespaces arrangement adult fine. app compiles fine, problem only shows adult parsing xaml. anybody seen something this? any ideas causing this? ideas debugging it? thanks!

<window x:class="osgviewer.osgviewerwin"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:int="clr-namespace:system.windows.forms.integration;assembly=windowsformsintegration"
    xmlns:myns="clr-namespace:myglobalns.myns;assembly=myassembly"
...
        <int:windowsformshost x:name="m_host">
            <myns:cmyclass  x:name="m_myclass" />
        </int:windowsformshost>
...
</window>