CMS Cannot upload image attachments
 

First of all this is a clean 4.0.1 install and no templates are modified.

I was upload to upload two textfiles using the attachment manager but when I try to upload three tiny png files the screen stucks at the following :

http://i48.tinypic.com/5kp0ms.jpg

I left it for a few minutes but the progress bar remains and nothing changes .. I have the same problem uploading just one file