TestExecute 10 - Can't run /SilentMode from CMD

I created a very simple project that opens Windows Calculator and closes it. It is bound to Source Control Perforce P4V.

I can run it in CMD without /SilentMode, but not with /SilentMode. When I call TestExecute, it doesn't load in Task Manager Processes. Am I missing something?

[Please see attached screenshot.]

The project runs fine in TC10 and FinalBuilder7.