No, you cannot retrieve IExchExtXXX interfaces unless you code is an ECE.
Nothing however prevents you from leaving from the ECE code intact (it
should work fine in Outlook 2007) and implementing a COM addin in the esame
dll or even in the same class that already implements the ECE functionality.

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

"Nikolas" wrote in message
...
Hi,

My company had in the past developed an Outlook addin for versions of
Outlook 2000-2003 with Exchange 2000-2003. A dll was created implementing
the
usual interfaces: IExchExtCommands, IExchExtUserEvents etc. and
registering
it with Outlook. We were using the Outlook custom forms. We wanted to use
form regions and create the same addin using VSTO. However, we didnt not
want
to re-write all the code that had to do with the controls of the forms
from
scratch. So we decided to keep the old dlls (without registering them) and
use them as stand alone dlls.

My question is: since the old dlls are not getting registered with Outlook
their events ( for example: IExchExtCommands:oCommand(LPEXCHEXTCALLBACK
lpeecb, UINT cmdid) ) are not getting raised. Is there a way of raising
these
events manually? Is there an object of the Exchange (or something that I
can
pass in as the 1st parameter in the above example function) that I can
retreive from the Outlook Object Model and call them manually?

Any help would much appreciated.
If any more information is needed please ask.

Thanks
Nikolas