Clear your winfilecache .dat file from your local users configuration folder and it should resolve this issue.
You can find a lot of instructions on how to do it on this site.
Make sure Dreamweaver is closed then open windows explorer and browse to: %appdata%
That will take you to your user's application folder. From there drill down to Adobe and the version of Dreamweaver you are using. Go to the configuration folder and find the file that begins with winfilecache, then has a large number and ends with .dat.
Delete that file and re-open Dreamweaver and I think the errors will go away.
If not, try reinstalling the latest version of the extension. It could be conflicts with the version of Dreamweaver you are using if you have an older version of the extension installed that would be fixed in the latest.