Hi, I'm hosting a web browser control and implemented IDocHostUIHandler in the GetExternal method I return the host object (QI to IDispatch of this). This application is running on XP In the web browser I load a page that calls the external object : window.external.doSomthing My problem is: For any user who is not belong to restricted user group(users group), eg. If the user login as a standard user(power users group) or administrator, the program runs ok For any user who is a restricted user(belong to users group), I get a javascript error "An error has occured in the script page. Library not registered" when executing window.external.doSomthing Does anyone have any idea?