Well I’ve been chasing this for ages. Sort of embarrassed that I hadn’t chased a stuck ‘Esc’ key message that Total Commander flags up. Usually pressing the escape key fixes it! Damn it, it’s a generic Windows 7 problem !!!!!!!!! So if you find you can’t ‘drag and drop’ with Windows 7 , just try toggling your escape key a couple of times. It works for me ;-) Thanks once more to NickP for the diagnostics… Check this link

http://www.sevenforums.com/general-discussion/15038-i-cant-drag-drop-4.html