I had this problem and searched high and low for an answer. Finally I have found it. See if this works ... (presuming you haven't already solved it)

With Dreamweaver closed -

Apparently the problem is caused by the toolbars ..I managed to solve the problem by renaming "toolbars.x ml" to "toolbars.xml.o rig" in this folder: C:\Program Files\Macromedi a\Dreamweaver MX\Configuratio n\Toolbars
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