Filefield upload boxes not shown at page load in IE7

I have encountered this issue after running final tests in different browsers.
When displaying edit form in IE7, filefield table, where draggable rows allow to browse and upload files, is not being shown, since it is correctly depicted in the rest of IE versions and in other browsers (Safari, Mozilla and Chrome).
Javascript is rightly enabled and allowed, and security settings are set to the Middle-Low preset.
However, I discovered that applying any change in the Internet Settings menu, in some way, repaints the page, and the filefields appear at once.
Then, if page is reloaded, the filefields are not shown again.

I've uploaded a short video with a demonstration: http://www.youtube.com/watch?v=EzyUbDhZ420

I didn't find anything similar surfing through the issues repository.

Please, any suggestions to get me back on track?

Thanks