My b2evolution Version: Not Entered

Hi all,

I use Windows Live Writer (latest version 14.0.3913.522 en downloaded yesterday). I created a new post and wanted to upload but I got this error message:
Picture upload not supported by Weblog
The following pictures cannot be published because the weblog does not support picture publishing.
http://img244.imageshack.us/img244/6938/200807243ic1.png

In the file types global settings '.png' is an allowed extension. I could also upload it manually using the blog. When I remove the picture it works fine. Where else do i need to configure something?
Thanks