I have been using Dreamweaver CS4 for some time now, but I just opened the program and got that error. If you are experiencing this error it’s likely that your layout files were corrupted.

I have been getting this xml parsing fatal error: stating that the file Designer.xml could not be read. Here is the easy fix:

  1. From any explorer window or your control panel. Click Tools>Folder Options. Click the View Tab. Click ‘Show hidden files and folders’.
  2. Depending on your OS navigate to C:
    Data/Adobe/Dreamweaver/en_us/Configuration/Workspace. Create a new folder
    and move all the files in that directory into this new folder. Restart
    Dreamweaver and you should be back in business.

Please let me know if this helped anyone!