Hi

On one laptop we experience a very strange behavior... it happens when we try to dock back a specific toolwindow by dropping it over any of the docking "icons". If we do it using the "Dock" option in the menu it works fine, no problems. We are using Actipro Docking components and the only control inside the ToolWindow is the WPF Diagram.
Actipro said they don't use COM so the error is not coming from them... therefore I ask you too... maybe you have an idea..

The error thrown is:

Exception from HRESULT: 0x88980406

System.Runtime.InteropServices.COMException (0x88980406): Exception from HRESULT: 0x88980406 at System.Windows.Media.Composition.DUCE.Channel.SyncFlush() at System.Windows.Interop.HwndTarget.UpdateWindowSettings(Boolean enableRenderTarget, Nullable`1 channelSet) at System.Windows.Interop.HwndTarget.UpdateWindowPos(IntPtr lParam) at System.Windows.Interop.HwndTarget.HandleMessage(WindowMessage msg, IntPtr wparam, IntPtr lparam) at System.Windows.Interop.HwndSource.HwndTargetFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)

Source: Presentation.Core

at System.Windows.Media.Composition.DUCE.Channel.SyncFlush() at System.Windows.Interop.HwndTarget.UpdateWindowSettings(Boolean enableRenderTarget, Nullable`1 channelSet) at System.Windows.Interop.HwndTarget.UpdateWindowPos(IntPtr lParam) at System.Windows.Interop.HwndTarget.HandleMessage(WindowMessage msg, IntPtr wparam, IntPtr lparam) at System.Windows.Interop.HwndSource.HwndTargetFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
 

It is a Win7 Terra laptop with .NET 4 installed.

Do you have any idea why is this happening?

That was first thing we tried, as described here (we target .NET 4): http://blogs.msdn.com/b/jgoldb/archive/2010/04/12/what-s-new-for-performance-in-...

Now we can reproduce it on another laptop too (XP this time)

We could reproduce the problem with toolwindows without Mindfusion components inside.

That means case is closed here 

Thx for support. Topic can be closed.