WordPress 3.6 Menu Problem

I just upgraded to WordPress version 3.6 and now I can't drag and drop my menu items anymore.

Pls, I need any help or suggestions urgently.
I have deactivated all my plugins and I still have the same issue.

Did you try deactivating your current theme and enable a WordPress default theme (like twenty twelve)? If the issue disappears by doing this, then the issue is in the theme - it may be that your theme uses an older coding approach that doesn't work in 3.6