Adding media not working

I am trying to add a picture (.jpg) to a page, I have uploaded the picture into the library, I have selected the size and the alignment but nothing is showing up on the page. When I go through the process of attaching the picture I get to the point where I click on “Insert into post” the windows goes white and then just sits there, I have to click on the main page behind it for the window to disappear. If I go back into the media library it shows that the picture is attached to my page.

Any thoughts??

Tim