Try recreating the users configuration folder.
this is the folder that contains the DW cache file.
With DW closed, rename the configuration folder to any thing like Configuration_bak.
Next, open DW to recreate the configuration folder, Close it again and open the extension manager.
In the extension manager, remove all extensions. Then install only the deprecated server behaviors extension:
open DW and confirm that you have access to the Server Behaviors, then close DW again and install the other extensions.