I am running Windows Server 2012 R2
I created a basic task to run with the action, "c:\php\php.exe c:\inetpub\wwwroot\support\api\cron.php". When I tell the task to run I get a pop up box asking "How do you want to open this type of file(.exe). Look for an app in the store".
I have other tasks that use .exe programs in their actions and they run without problem.