This function is called before loading a URL  to allow you an opportunity to modify the URL.

In the following  example the user is only allowed access to local stored files. If a link to an internet-site is clicked, we want a file "DontDoThis.htm" to be shown.

Similar lines of code could also have been placed in OnBeforeNavigate2 but there is an important difference: OnTranslateUrl is not called when you use Navigate or Navigate2 but only when a hyperlink is clicked. So in this example you could still let a speedbutton call EmbeddedWb1.Go('www.somewhere.com') without  redirecting the user to "DontDoThis.htm".