> I have a Windows client (Vista) that registers a number of callback
> objects with a Linux server in the way described in the book 'Advanced
> CORBA Programming with C++' (Chapter 20):-

> module CCS {
>   struct CallbackInfo {
>    :
>    :
>   };

>   interface Callback {
>     void notify(in any data);
>   };

>   interface CBRegistration {
>     void unregister();
>   };

>   interface xxx {
>     CBRegistration register_callback(
>       in Callback cb;
>       in CallbackInfo why;
>       );
>   };

> };

> When the server makes a callback, this sometimes works ok but other
> times it fails with an OBJECT_NOT_EXIST exception.
> After one failure, it appears that the other registered callbacks also
> fail in the same way.
> When the Windows client subsequently exits, it still manages to
> successfully call the server to unregister the callbacks. It does this
> by calling the unregister() method for each of the callback objects in
> turn. This proves that the callback objects still exist on the client
> and have not been inadvertently destroyed.

> When I use a test client running on the same Linux machine as the
> server, I don't see the problem.

> I have added debug to log the exception minor code (using e.minor() )
> - this is set to zero.
> I have added a few retries with a delay between each but all the retry
> attempts fail in the same way.
> I have tried changing some configuration parameters such as
> verifyObjectExistsAndType, lcdMode, strictIIOP.

> We are using omniORB 4.0.7.
> Linux server is running under Kubuntu 7.10.

> Any help greatly appreciated.

> Regards,

> Brian.