I opened one instance of Reader and get the two same processes.
Process.Start(...) do the same thing and returns window handle which is NULL but second process has correnct HWND
Is that should work in that way?
The thing is I just open Adobe Reader application and do not perform any actions
Provided solutions does not help.
I still getting two processes of Reader aplication if I just open it.
This is by design if the "Protected mode" option is on.
The first app has no HWND or interface, but can access all files.
It starts the second app in a sandbox, which can access no files. It has all windows and HWND.
The first app controls access to files for the second app. This is called "Sandboxing" and many apps now do this, especially web browsers.