Invoking context menu from elsewhere

Jon B.1

Hi folks -- I'm working on an application which stores data in a non-Dropbox folder, and sometimes syncs the contents to a Dropbox folder.

I'm already implementing a Windows context-menu handler for my app, which appears when you right-click the non-Dropbox folder -- and I'd love to include some sort "Share on Dropbox" menu item, which brings up the standard Dropbox-client sharing GUI.

My idea is that, if my non-Dropbox folder gets right-clicked, my handler can pass a call directly to the *Dropbox client*'s context-menu handler DLL (assuming it uses the Windows standard interface), substituting the path for the corresponding folder in Dropbox; Dropbox's handler should then respond as if that folder were right-clicked.  But to do that, I'd need to know where to find the correct Dropbox DLL.

Any clues where in the registry I can find this?

(Explanations of why my idea is obviously insane also gracefully accepted.)

Jon B.1

Further notes on this, for anyone's reference :

In the registry, HKEY_CLASSES_ROOT\*\shellex\ContextMenuHandlers\DropboxExt contains the handler ID {ECD97DE5-3C8F-4ACB-AEEE-CCAB78F7711C}. 

There's a similar value under HKEY_CLASSES_ROOT\Directory\shellex\ContextMenuHandlers\DropboxExt .

Under HKLM\Software\Classes\CLSID\{ECD97DE5-3C8F-4ACB-AEEE-CCAB78F7711C}, there's an InprocServer32 subkey with a DLL path (e.g. DropboxExt64.28.dll).  Is this the DLL I'm looking for?