# Other .NET Programming > Windows Presentation Foundation (WPF) & XAML forum >  WPF Window.Activate() Returns False

## Ssebu

Hi all,

We've got an application that, when started, displays a login window. We'd like the window to be the active window, and the focus to be on the username textbox. We call the Activate() method in our overridden OnContentRendered method, which works fine most of the time, but sometimes it fails, and returns false. In particular, it seems to always fail on virtual machines. In cases where it fails, the application doesn't have focus (even if we set up our Login form to be top most) but the button in the task bar flashes.

Does anyone know what might cause the Activate() method to return false ?

----------


## boudino

Why not to open it as modal dialog? It could be safer.

----------


## Ssebu

The dialog IS modal (we use ShowDialog() ), so maybe also setting it top most was a bit overkill, but since we were having focus issues, we threw everything we could think of at it. I believe NOT making it top most doesn't fix the issue anyway.

----------


## boudino

Do you use just ONE gui thread (the one in which message loop runs), or more (e.g. for splashscreen)?

----------


## Ssebu

The login window itself is shown in a separate STA thread.

----------


## boudino

I think this could be the case. There are problems with focus if there are more than one thread where message loop is running.

----------

