2 Errors on Dreamweaver start with Java script

Hi,

When i start up Dreamweaver CS4 I get the following message, can any one help please.

Also when I go to run WebAssist this message also pops up

The following JavaScript error(s) occurred:

Unable to open script file “C:/Program Files (x86)/Adobe/Adobe dreamweaver CS4/Configuration/Shared/WebAssist/Library/WA_UI.Js” (error 3)

Any help would be very much accepted.