RegisterKeyStateNotication failed during Load a DLL at runtime

See more:

.NET2.0

C#2.0

C#

.NET

Mobile

DLL

hello

i try to load a DLL at runtime in my c#.net 2.0 cf app for a wm 6.1 device. See the following code

//full dll path
string dllPath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) + "\\" + SymbolKeyboardDLL;
  
//load dll
System.Reflection.Assembly asm = System.Reflection.Assembly.LoadFrom(dllPath);
  
//get type
Type keyPadType = asm.GetType("Symbol.Keyboard.KeyPad, Symbol.Keyboard, 1.6.1.7, Culture=neutral, PublicKeyToken=null"
);

//try to create instance (Exception occurs here)
Object pad = Activator.CreateInstance(keyPadType);

here are the exception details:

Symbol.Exceptions.OperationFailureException: RegisterKeyStateNotication failed
at v.h()
at Symbol.Keyboard.KeyPad..ctor()
at System.Reflection.RuntimeConstructorInfo.InternalInvoke()
at System.Reflection.RuntimeConstructorInfo.Invoke()
at System.Reflection.ConstructorInfo.Invoke()
at System.Activator.CreateInstance()
at ButtonCheck.Form1..ctor()
at ButtonCheck.Program.Main()

does anybody why the exception occurs ?

thanks for any help!