Looks like the users configuration folder has become corrupted.
recreate the users configuration folder as outlined in step 12 of the Adobe troubleshooting guide:
http://helpx.adobe.com/dreamweaver/kb/troubleshoot-javascript-errors-dreamweaver-cs4.html#main_user_config
after renaming the configuration folder, open Dreamweaver, and go to Commands -> Manage Extensions to open the Extension Manager, once the Extension Manager is open, close Dreamweaver.
In the Extension Manager, select each extension and uninstall them, then reinstall the extensions.