yahoo mail beta attachement problem


New Email
Using Vista Ultimate, IE8 & yahoo mail plus paid veriosn. When using All-new Yahoo! mail, the window that open for file attachement is of original Vista type...means with links to recent places & recently changed at left bar & folder view toggle switch on top right. When upgrading to yahoo mail beta, the windows that open for file attachements is no more same as in classic or "All new yahoo!". The link for recent places, recently changed etc are missing & also the folder view toggle icon does not perform same gives drop down options rather than toggle with each click. I tried IE with add-on disabled.....then then it solves the problem.
Have tried Win7 & IE9 Yahoo mail classic & beta opening the attachement window of win7 system. But all-new yahoo! opening again less utility file attachement window.
I am not sure if i am able to explain the actual problem i am facing, but some have experienced same problem would easily understand what problem it is. Pls. suggest if some IE add-on is the probelm, or some setting in yahoo mail can rectify this problem. Pls. dont suggest use chrome or firefox.....this probelm appears irrespective of explorer type.