If you know the AppID you can look that up in the registry.

See AppID Key.


You should be able to find that by registering your ActiveX EXE and browsing to it using the OLE View utility. Look for it in the "All Objects" branch of the treeview in the left pane.

Then you can hard-code that in clients to use a simple registry query to see if it is there:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\AppID\{AppID_GUID}