Error while enhancing a Window.

Hi experts,

I have enhanced the component BT111S_OPPT the view Result but when I am trying to enhance the window MainWindow, it is giving me the followin two errors :-

1> Context cannot be enhanced

2> Generation of derivation classes failed.

When I am clicking the long text beside the first error, the following information is showing up :

MESSAGE No. - BSP_WD_TOOLS094

Diagnosis - The implementation of method WD_CONTEXT_CREATE, which is used to generate the context, does not match the expected code pattern. Therefore the automatic exchange of the context class is not possible.

System Response - The enhancement is terminated.

I have searched OSS notes with the message number but found no result. Can anyone help me out of this?