I would like to mention here that the function extension manager sometimes gets damaged for inexplicable reasons. In this case, just reinstall the function extension manager. The first time installation and reinstallation methods are the same.
In the Macromedia installation software directory, double-click the Function Extension Manager installation icon.
Complete the installation of Function Extension Manager.
Click the "Install new extension" button in the extension manager.
Select and install the plugin.
Select the plug-in in Dreamweaver . In the example is the FlashImage plug-in.
Set up the plugin.
The Macromedia website also has many plug-in downloads.
http://www.macromedia.com