setfocus - How can I find a given window on the client computer and activate it from ASP.NET -

To run a website from asp.net, I need to move the control (focus) into a Winforms application.

If the application is not running, then I know that I can use the process.start () method .

But if the application is running, I do not want to launch a new window.

I have the option to set a humble application as a unique example, but what if it is a foreign application? I meant that if I am not an author and there is no control over launching new examples ...

How can I find the window given on the client computer and activate it with ASP.NET For security reasons you can not do that code inside the browser does not have access to the user system.